Ocon is going to stay with Force India, which will only at best change name. Stroll is not going to Force India, they're committed to Williams, and there's simply some situations that lead up to false interpretations.
Lawrence Stroll, Lance Stroll's daddy, is a businessman and being involved in F1 has his ears closer to the ground, which means he gets information easier and in this case the possibility that Force India is open for investment from additional parties, which is surely the reason for the name change. Force India is constantly doing fantastic, has a solid base, capable personel and drivers, and if more investment/resources are available to them, have the potential to make another step forward from P4 to even P3 in the WCC.
There's a humongeous business oppertunity here, and it was relatively blocked or less interesting due to the team carrying the 'India' name, and perhaps not limited to the involvements / issues surrounding Dr. Vijay Mallya. Since Stroll is a businessman who knows what he's doing, AND has plenty of money to throw at things personally AND businesswise, has probably raised interest in the Silverstone-based Force India team and might 'buy' into them which would mean he gets an additional platform to Williams and his son. It would benefit Force India since it would get them more money so it would get them forward, and it would benefit Stroll camp for business opportunities. Nothing more, nothing less.
Media is then 'inventing' or making clicbait stories that this means driver Stroll will leave Williams to go to Force India. I'm confident that won't happen at all. He's just there, he's developing, and it makes no sense to shift to Force India now. Perhaps in the future, perhaps 2019-onwards there might be room, but as of now, there is no such thing.
Ocon will not be free either way, as he will remain a Mercedes protegé either way.
Romain Grosjean will not go back in a million years to Renault. He doesn't want to and nobody at Renault wants him to come back. Grosjean's F1 career is ending and his only option is to stay with Haas for next year and afterwards, he will only be able to go to Formula E or other racing classes like WEC, Indy, LeMans and that's it.