The Pro 2 is no more the new Mono Evolver Keyboard than the Prophet 12 is the new Poly Evolver Keyboard. These are totally different instrument lines, and the mere fact that they're both hybrids means very little. The Evolver line has not been replaced, and it remains an enthusiastic topic of discussion whether or not DSI will ever actually replace it.
When the Pro 2 first came out, I pressed hard for a module version. To this day, I still wish it existed, because if it did, I would make a Pro 2 Keyboard-Module pair my definitive longed-for mono synth. But DSI has repeatedly said they will not produce a module version. Anyway, if they were going to, it certainly would have happened by now. They always announce a module version well within a year of presenting a new keyboard synthesizer, and the Pro 2 has been out for several years now.
On the other hand, there are sometimes surprising discrepancies between what Dave Smith says and what Dave Smith does, so no one of us can say for certain. Personally, I would be thrilled if DSI finally produced a Pro 2 Module, but I'm not expecting it to happen.