Could you explain something? How could shares available to borrow thereafter “taken out of the equation,” be used to “cover immediately.”
Forgive my ignorance, but don’t they need to buy shares to cover?
The only way I can see your third (above) theory making sense, is if they needed to locate shares to borrow, because they originally shorted with no located borrowed shares (naked), so now they first had to locate them, before they buy shares to cover them.