The desk margins against the average, never the last swap. Depth is not correctness: a pool priced wrong looks exactly like a pool priced right.

COIN has never had a multiplier scheduled. When one lands, the shorts pay it on the same block, without anybody sending anything.

Nobody has opened a market on this name yet. Opening one is permissionless and costs the gas: the desk checks that the token really is a Robinhood share, and that its pool remembers at least two minutes of trading.