It’s probably not dead. It does take a while to get on to the marketplace if that was the intended target as of late. While I’ve never used this plugin, I’ve watched several other WIP materialize from ‘Gumroad’ available plugins to Marketplace plugins and there is usually extra work the developers have to do in order to make the marketplace release compatible and compliant to Epic Games specs. 1-2 months in my experience.
Of course, hearing from the developers is what you really hope 