How to book ticket for Kawachi Fuji-en?

I found this page:
https://www.japan-guide.com/e/e4881.html

And of course, the link does not work. It has never worked. It's just a lazy affiliate link to the Japanican homepage. Doing a search on Japanican gets me nowhere either. So that's a dead-end.

I've also found this:
https://www.govoyagin.com/activities/japan-fukuoka-get-tickets-to-kawa...
And they manage to charge EUR 19,90 for the ticket, and there are reports of people having had to pay a surcharge at the garden, so this price should only cover the base fare. That means they manage to inflate the price 5-fold, which is frankly outrageous. Also with that kind of price, they are severely decreasing their credibility. So that's another dead-end.

I need to purchase tickets in advance, from a credible source for obvious reasons, and at a sane price. If I can't visit the garden, it will change my itinerary, so I cannot deal with the risk of them being sold out when buying them at a convenience store locally. So either I need to buy tickets in advance, or I need to know that this isn't possible. I can't just go and wing it.

I will be in Kitakyushu from 30 april to 3 may. That is set in stone, so to speak, because securing a good hotel is tricky during that time of year. Also I will leave the country after 5 may, so I can't just wait until reservations are no longer mandatory.

What are my options?

Did you read the page on
https://www.japan-guide.com/e/e4881.html
yet?

You can get the ticket at the convenience store like 7-11 or Family Mart indicating the date and time slot, but you still have to pay the rest when you get to the park - and the surcharge goes up to 1000 yen at peak times.
More info here:
http://bit.ly/2HIkPKJ

Did you read the page on
https://www.japan-guide.com/e/e4881.html
Yes, that's literally the first thing in my post...

You can get the ticket at the convenience store like 7-11 or Family Mart indicating the date and time slot
I already said something about that too:
"If I can't visit the garden, it will change my itinerary, so I cannot deal with the risk of them being sold out when buying them at a convenience store locally"

More info here:
http://bit.ly/2HIkPKJ[/
Not really actually. It has exactly as much information as I'd already gathered and summarized in my first post.

Anyone? Otherwise I have to assume making a reservation is impossible, and can only be done using magic.

https://www.tripadvisor.com/ShowTopic-g303160-i7635-k10382021-Kawachi_...
This topic shows this year's situation.
Kawachi Fuji Garden's advance ticket is officially sold only at domestic convenience stores. International tourists often ask their friends, family members or accommodation host to buy the advance ticket. When buying the ticket, you have to specify the date and 2 hours times slot.
Additional 500 or 1,000 yen is paid at the gate if necessary.

That means they manage to inflate the price 5-fold, which is frankly outrageous

What is outrageous is your arrogance and sense of entitlement. You sound like you think you would be doing the garden a favour by visiting them, and they should go out of their way to provide you with easy and cheap booking options. None of this is true; they already get more than enough domestic visitors.

It's just a lazy affiliate link to the Japanican homepage. Doing a search on Japanican gets me nowhere either. So that's a dead-end.

You display an arrogant attitude, indeed! If you read more carefully, you will notice that the page states that tickets "will become possible via Japanican." In other words: they are not not yet available, but they may become available in the future. Last year, it wasn't until mid April that Japanican started offering the tickets; however, I am not sure whether they teamed up with Japanican this year again.

What is outrageous is your arrogance and sense of entitlement. You sound like you think you would be doing the garden a favour by visiting them, and they should go out of their way to provide you with easy and cheap booking options. None of this is true; they already get more than enough domestic visitors.

I'm willing to pay, so I should be able to get a ticket, somehow. But I'm assuming you think I'm like "everything should be available abroad!" and that isn't the case. What do you care if I sound arrogant? I just want something arranged for my holiday, and I'm willing to do some stuff to get it done. Is that so bad?? The problem is dat japan-guide suggests to promise of ticket availability through Japanican, and there just bloody isn't. Japan-guide is the one being arrogant in keeping that passage of text there, even though is it clearly a way to attract clicks, since it's nothing but an affialite link to the Japanican homepage. Anyway, if a promise is made, I should expect a proper followup. If no such promise is made, I would surely take a different stance toward Japan-guide & Japanican.

You display an arrogant attitude, indeed! If you read more carefully, you will notice that the page states that tickets "will become possible via Japanican." In other words: they are not not yet available, but they may become available in the future. Last year, it wasn't until mid April that Japanican started offering the tickets; however, I am not sure whether they teamed up with Japanican this year again.

Will not be possible via Japanican. And Japan-guide darn well knows this. Mid april is of zero use to anyone, because that's near the end of the reservation-only period. "will become possible via Japanican" suggests a promise, and it isn't going to be kept. Where I come from, if you make a promise, you keep it. Period. So yes, of course I'm a bit moody toward Japan-guide for this.

This topic shows this year's situation.
Kawachi Fuji Garden's advance ticket is officially sold only at domestic convenience stores.
You sure about that? If that's really the case, it makes me question the validity of overseas-bought tickets, and by extension the trustworthyness of them ticket services (like the one mentioned), even further. Including Japanican.

It seems tourists from mainland China, South Korea, and Taiwan often ask their friends or families living in Japan to purchase advance ticket at normal price. I hear other international tourists asked accommodation hosts or hotel concierge to bus one in the last 2 years. Advance ticket system has been introduced since 2016 season.