Perhaps if one placed high voltage onto the USB D+ and/or D- pins?
That doesn't seem very likely, unless the PC USB port was putting out high voltage.
How often does a PC USB port do that? They're probably fairly bulletproof, given the
hazards a PC faces day to day. Otherwise, OP would have to be sticking live wires into
the USB connector. Also, the UNO boards have some protection on the D+,D- pins.
I'd bet OP has some "other" problem, and has possibly wrecked the bd in the meantime
by resoldering the USB chip. I'd not want to try an resolder such a tiny pitch part.