There are secondary markets for shares in privately held companies. I signed up for one but I never followed through and did anything with the account so I can’t describe the process. I disagree that OP won’t find anyone willing to sell. I expect many people will jump at the chance to unload their shares.
Those that have shares paid 54.20 when the market price was in the low 30's. They didnt have to buy them at the inflated premium (or convert them from their original holdings), why would they sell them now?