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So you are suggesting him to file a case for it. For 2100$ it will cost more than it. I think he should wait because that company says that they will look at it. That means they have the private key of that wallets and they can recover that funds. It will be better to wait and give them some time.
The company said he need to meet an expert (e.g. lawyer, legal advisor etc) of course it's need a lot money to get help from them. It's different scenario as you said to wait, if the company able to recover it personally without an expert, why they need to tell him to meet the expert first?
Even the company has the private key, that doesn't mean they able to recover the coins. Take an example of Coinbase, centralized exchanges always have the customer private key. But when there's some people has a same case of send coin to wrong address, they said they can't recover it. If you don't believe me you can search it yourself in this forum.