I have the same problem as well… and cant find any soluiton. I am wondering if theres anybody who hasnt got the same problem? Is it ment to work at all in packaged project? Maybe it is only for virtual production and capturing animation not for builded project? Would be nice if Epic could confirm that it ment to work in runtime as well not just in editor…
Ok so i found a solution for this.
First off, this is not a collision problem. The problem is with the hair’s physics simulation not activating in the packaged build (only in standalone or PIE).
The fix is pretty simple but pretty weird tbh. just find out what’s your game’s “Default Level” in the project settings. (The first level that loads up when you open the game)
And place a character that uses groom anywhere in the world. i personally hid him below the floor. this somehow forces the packaged build to load the groom simulations upon initializing and all groom simulations will work on any level and any other character. (it doesn’t matter which character you place in the first level aslong as he is using groom with simulations turned on, all the rest of the character’s hair will work too and like i said on any different level aswell ^^)