This is yet another serious problem with closed source wallets, we have absolutely no idea what they are doing. The BIP39 to BIP32 or even the BIP32 implementation may be severely flawed and be deriving a wrong key (maybe even a weak key) at a known derivation path! Which may explain why none of the paths that were tried so far work.
Anyway, If you can get the xPub of your wallet there is a tool to scan the wallet if what derivation path your bitcoin address belongs. But you must deposit a small amount first on that address so that it could scan the used address including the derivation path.
This also ONLY works if your derivation path had absolutely no hardened indexes which may not be true since someone
here claims they told them the derivation path is m/1'/0/0, m/1'/0/1, m/1'/0/2 (although none of them worked with OP's mnemonic).