TechnipFMC is a newly joint company right?

IMHO, a newly joint company doesnt really have a fixed working environment or benefit yet. It will inherit the former company env. & benefit, but expect some "turbulance" for this few starting years.

seniors/managers from both company will bring their old habit together in this newly form organization, and both will try their hard to win. It will take years before it became stable again, then you can talk about the environment and also benefit.

I can be wrong, but believe me, you need to learn the skill to survive and adapt without taking sides between those parties.