Get equity or get out - make the promises binding.
On top of that, being the only technical person and have full control over everything, including domains, hosting, code, etc. It's not really like I can be forced out.
You were paid for those things. You can't hold them ransom.
That you don't know pretty much guarantees you have zero legal control. I assume the corporate entity is not in your name. Domains, hosting, etc are all very easily gotten from you by a single letter from a lawyer. You will likely hire your own lawyer, and you'll essentially be paying him to tell that you have to cough up, because you'll lose in court, in addition to tens of thousands of dollars and a ruined reputation.
Holding this stuff hostage would not work out well and should not be considered a contingency plan.