Yes she's completely frozen for the rest of the basement I believe. Doing the processor, getting the third joint plug, and going back for the other two, she won't move ever until she reappears at the scripted scene with the elevator. I think if there was a place where it could be done earlier on in the basement it'd be more useful but I haven't done any testing.

I posted this to reddit already so I'll link the post that has the video. Basically I found a glitch that froze Marie in place in the basement but I think it's too situational to have any use case, Idk though since I'm not a speedrunner. I explained my steps in the post itself.

https://www.reddit.com/r/ResidentEvilRequiem/comments/1rzb6c5/frozen_marie/