This will not be an issue with Monero unless you also share the view key which I would not advise for this reason.
Hopefully, it will not come down to that. If it does become an issue, here are a few soltions I would suggest.
- Putting in the sidebar that whoever claims a donation first will be added to the thank you list. And therefore you should message the admin just before or just after sending the crypto. And even having a time limit on claiming a donation to prevent others claiming an anonymous donation such as 1 hour. I think the best option is messaging the admins before the transaction is made and after the transaction is made with the transaction ID.
- Some crypto wallets support adding messages when sending the crypto and the user can place their username in the transaction message. Add in the sidebar to be added to the thank you list, you need to embed your username in the transaction message. The downside to this is the username is embed in the transaction on the blockchain forever.
Will EA App work in Wine v9?