Vertex stuck during cloth animation on rigged model

Question

On a model ripped from a game, I separated the outfit from the body to make it easier to rig.

Now I want to attach the outfit back on the body, here are the two meshes :

The main body :

And the outfit itself :

I parented the outfit to the armature and used the "transfer weight" function from the main body to the outfit.

I want to give the lower part of the outfit a cloth physics, so I applied the cloth modifier to the whole outfit mesh, with the upper part as pinning group.

But when I animate the model, deformations of the cloth appear and they don't make any sense to me, see for yourself :

The more I lower the end of the "pinning group", the more spikes I get, so I guess it's related to bad weight attribution, but I can't see any problem when I switch to weight paint mode.

edit:

Answer 1

There are just too many conflicts in this file and the structure does not make it easy to try resolve.

To start / you have a vertex group called Dress assigned a weight of 1 that does what exactly? Nothing that I can see and would just remove it. A lot of the other vertex group came along for the ride with your transfer, like the fingers. You don't need those vertex groups in your outfit. You also have geometry overlapping like the cloak that is part of the Main Body object and the Outfit object which does not make things easier to understand.

If you select your rig and activate the 3rd last layer you will get your deform bones. Select the chest bone in pose mode and then the outfit before going into Weight Paint. You will see the weight painting is not that successful... and the weight group also makes that clear...

A few suggestions. Work in Solid mode as it is easier to see. Ctrl N - will turn your normals all the same direction which is never a bad thing. Automated proccesses seem like a good thing but can also cause more work as you have to clean them up.

Guess you know you are being quite ambitious to try so many things at once?