However, people can at most proof that they did deposit some CFC to ShareX. It is more than unlikely they can show proof they didn't sell their ShareX holdings and then withdraw BTC afterward
Not that hard to track via the blockchain explorer, I'm confident I could track this.
Harder to prove any bought on the exchange but not appearing in ur online exchange wallet address.
In my case I'll be just claiming those I sent to the exchange for the swap (luckily for staking purpose most the times earlier I bought I'd sent back to my wallet), any bought on the exchange that I can't now prove I'll just write off as lost (none of which is in anyway coffeecoin's fault) along with the various other coins I lost in sharex including some btc

Nope. I do daily trades on exchanges and I'm sure blockchain explorer cannot track this
The problem is that if people did sell their CFC holdings on ShareX, blockchain explorer still showed no change of their balance as long as the new buyer did not withdraw
No offense but it's how blockchain explorer works. Nothing can be tracked if no new transaction on the network
That means our dev can only know these coins are still on ShareX, but he cannot know who is the owner of the coins
Too long detailed and too tired to explain here, but I'll explain more to the dev, I can map out through a combination of the block explorer and my trades, to know the how what where of sharex's wallets, and I was going to suggest (others have already similar), the dev can hold the coins until after a period and no complaints to make sure less chance of people claiming who had sold.
also like this:
"As of right now, all that comes to mind is taking claims for ShareX deposits within the time range of ShareX V1/V2 swap participation confirmation, and the date ShareX went down. Anything before that would increase the likelihood of that claim including sold CFC."
somewhat narrows it down to the people who only sent in for the swap.