The process was fine for me, just had to wait. It also cost nothing. IB (interactive brokers) is also cheap to trade - I haven't traded.
If you think Sezzle might get taken over by a bigger fish there will be no brokerage costs I believe, just need to hold on to your shares - maybe sign a form to transfer them depending on what the company announce on Monday. They might set up a share sale facility for other folks who want to sell.