Got COE from company. Second thoughts

Hi. Guys. I applied for company a while ago and I started having second thoughts about them when I saw a recent youtube video...I also read horrible reviews about them. I had no idea they had started and finished my COE application...They haven't mailed me my COE yet. I am a little worried and stressed about what to do.

I applied to some other companies...like Interac, Peppy kids, and Aeon and have all been invited for the in-person interviews.If I passed one of those I would rather go with them than this company...

My question is...what will happen if I cancel on the first company..? Would I be under able to get a COE from another company...? Like if I said I am just no longer able to go to Japan for whatever reason. Also I read somewhere that a COE expires after 3 months if you don't apply for the visa...Is that true?

Any advice on what to do and what could happen would be appreciated!

http://www.japan-guide.com/forum/quereadisplay.html?0+94906

I know this thread is old, but your situation sounds a bit similar. Please think about it.
Has your first employer candidate already TOLD you that they already got the CoE ready for you?

Yes, they said it came in the mail recently. I never knew they even started it because they gave me absolutely no idea when my start date would be before...

But in any case, you already said (some time ago) YES to their offer, correct?

I saw that thread when I dug deeper. So if I get an offer from one of these other companies I would have to tell them obviously, but I don't know what would happen in that case. I know people get cold feet about going to Japan or have to cancel because of a tragedy so I am assuming there is a way to cancel it...

Everything started happening all at once. After months of no contact I heard back from all these other companies who seem like better choices..

It's weird. Because I never signed the final paper that I was given.. I said yes to the provisional offer I was given but actually never signed the next step.

I see on the embassy page it says

"Please note, however, that even if a foreigner possesses a Certificate of Eligibility, an embassy or consulate will not issue a visa in certain circumstances -for example, if there has been a change in the situation since the issue of the certificate (such as the company that was planning to hire the foreigner deciding not to do so because of business difficulties) or if it becomes evident that the documents submitted to obtain the certificate were false"

So sounds like they could cancel it