This is all based on my understanding, I can't provide any source to what I'm saying.
I believe Scientific Games owns everything related to Bally/WMS. Chicago Gaming made a deal with them. (Maybe Planetary Pinball is involved somehow, not sure.)
Gottlieb IPs are owned by Gottlieb Development LLC.
I see no reasong why wouldn't Stern have the rights to older games.
Stern also have the rights to Data East games.
The only issue they would have with remakes if the game in question was based on a license, in which case they would need to get the rights for that if they wanted to remake something.