Got it, @RobertB4444 so to summarize even though I previously was fully paid out and reflected the gain then , I would show a loss for the additional $10 now
-2016 Exercised/purchased 100 shares for $100
-2018 Acquisition led to payout of $500 for the 100 shares --> $400 gain
-2023 Escrow settlement additional $10 --> $90 loss for tax year
