Jetfoil Yakushima: Reservation via web site?

Hello,

I am looking for a way to book a jetfoil Kagoshima to/from Yakusima in advance (mid-May). Reservation via www.tykousoku.jp is in japanesse only and I think they would accept bank wire transfer as only payment option.
However I have found the site:

http://www.directferries.com/kagoshima_ferry.htm

and it seems they offer the reservation I am looking for and a payment via credit card. Do you think it is safe to use this service and the crew in Kagoshima jetfoil port would recognize the confirmation of the reservation I got from DirectFerries?

Thank you all for a great resource on Japan!

Reservation for the Jetfoil could be unnecessary, they are not likely to be fully booked.