Just my opinion, but using logic as a basis.
Your broker, whether ST, Ameritrade, E-Trade, etc, took it upon themsleves to fill your order.
The hedge funds who are short are out of the equation as far as you are concerned, because I would be quite sure you do not use a hedge fund as a broker.
It is therefore up to the brokers to fulfill your sell, same as they did your buy. Now, the numbers could be a bit crazy, bouncing all over the place, but those shares must be honored.
What takes place behind the scenes between ST and Nite or the other brokerages, we may never know, unless it becomes a public spectacle.
I hope this helps.
EDIT: Oh, and I wouldn't feel too sorry for the MMs who may lose their a$$e$ when all is said and done as they have made billions of dollars running small startups out of business the same way they tried to SPNG, through massive NSS. This is just a little payback for those times.
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