[Sylveste]

>Or maybe the better analogue is, how do you fulfill your end of the deal as a short seller and return the shares owed to your counterparty if the company disbands in the meantime?

If you're short a company and the company goes properly bankrupt then the shares are literally worthless paper, you just throw them away.

I've been in this situation with interactive brokers and the position just disappears. (You get the profit as though you closed the position at a price of zero.) Shares of something that doesn't exist similarly don't exist. They just vanish.