I can understand that Great Adventure would be in better shape if they didn't have to support this absurd, hydrologic-launched monstrosity every year. I get the desire to get out from under that burden completely. I also get that Cedar Fair has been severely burned by Zamperla on TT2.
I think the grand question here in my mind is whether or not Intamin is willing to renovate Kingda Ka for the new Six Flags with either a standard LSM launch or a swing launch with a back spike.
If Intamin is willing to take the project and it is the new Six Flags who is refusing to play nice with Intamin (as was rumored on TT2), I believe removing Ka would be horrendous mistake. Ka is, objectively in my opinion, incredibly valuable—both as a hunk of steel and as an icon for the park. The problem isn't the coaster, the problem is the launch system.
If Intamin is willing to replace the launch system and new Six Flags is allowing their pride/arrogance/anger/past frustrations/whatever else to cloud their judgement to the point of preventing them from working with the company who could be reasonably expected to make a renovated Ka function reliably and with far lower operating costs, that would be a major management red flag for me.
I believe history has now shown that contracting Intamin would have almost certainly been a far more correct course of action for Dragster and, if new Six Flags is still unwilling to acknowledge that after what has happened with TT2, that'd be pretty concerning to me.
Now, on the flip side, if Intamin isn't willing to LSM-ify Ka, I think the argument for the wrecking ball becomes much, much stronger, unfortunately. No other manufacturer has successfully and reliability built coasters in this tier of height/speed/etc. Contracting anyone else would be playing with fire.