The Federal Reserve, none other!, had to open the discount window to let these players borrow (through banks of course) enough capital to settle their trades and/or meet margin calls, or the CME almost surely would not have been able to open its doors the next day.
At one point during Black Monday, SP options were being quoted with a forty point bid/ask spread. One market maker was so harassed by various parties that he screamed at one of his would-be persecutors, ''Hey, I'm making the best market I can, you (bleep). If you think you can do better, here's my damned deck (of orders).'' The individual did not take him up on his offer.
A unique incident (so far) in financial history.
We researched to find quotes for a whole bunch of options - well-known stocks - for that week because a major player went under and we needed to calculate his net balance for each of those days. We couldn't - there weren't any quotes at all for many options.