Sent BTC to public key instead of my address
Seems there is a little confusion here: are you talking about private keys or bitcoin address in form af a public key?

Anyway in coinomi wallet you cannot display any kind of uncompressed xPub or similar keys, so he should have sent the funds to a proper BTC address.

Otherwise he tried to send BTC to a private key but this should be impossible by protocol definition. Even if the BTM scanner somehow accepted a priv key as an input the software should recognize the issue and would stop the operation.