So you're actually trying to make an altcoin mining pool work? Most altcoins' mining pool setups are very different from Bitcoin's as a result of them changing a lot of settings and principles related to how mining works.

If you would tell us for which coin you are trying to set up pooled mining for, we could offer better advice. Regtest will not solve your pool mining problems, it is a local network of nodes that don't broadcast to a public blockchain.