If the unit does not say it can handle 220v, then do not plug it in.
As soon as the equipment is witnessed to have a power transformer in it, which is partially indicated by the great mass of the unit, then it is designed to have ONE voltage used. Just one single voltage. It might have been internally re-wireable to handle 220VAC, but we’re past that now.
You blew it all to ratfecal, I’m afraid.
It is junk. Big time, junk. Dumpster material, for sure. I’m fanatical about saving gear..but that one is a perfect dumpster candidate.
I’ve fixed a lot of audio gear (thousands), and I do this as it gives me insight on the market, with respect to design vs execution vs time. I get to understand all the mistakes that can be made.
And I’d toss that unit, I’d not even bother to open it up .....unless I wanted to amuse myself with what electronic hamburger/chum looks like.