Tina was supposed to come back
https://weminoredinfilm.com/2014/03/21/13-things-you-may-not-know-about-friday-the-13th-part-viii-jason-takes-manhattan/
But she didn't because she asked for a raise, and she came up with a script that had elements of Dream Warriors. I guess that kinda explains Renee's visions, and the ending of the flood was probably meant to be Tina's doing. Would it improve this sequel if she did come back, I mean Jason vs Carrie in New York.