Power mesh track jumps on first tracked frame

I am trying to use mocha’s powermesh tracker to remove a leash over the fur of a cat. Technically speaking I believe that this ought to be a shot that should be great for tracking with powermesh. But, for the life of me I cannot get the track to work.
As you can see from the headline the first and most obvious thing that happens is that the mesh jumps to some random place on the first (attempted) tracked frame. Then, after that it either tries to track this new area, or becomes a garbled mess, or the track just fails completely.
Secondly, sometimes it just garbles from the get-go.
Thirdly, I have gotten one or two tracks that suddenly and magically works…ish. Those times however the motion of the leash is tracked into the mesh as well, which is precicely what I do not want. So I have a stencil shape for where the leash is, but Mocha seems very unhappy about subtracting that off of the overall patch.
The cat’s movement is just from a crouched position to a sitting position so nothing crazy is going on. I have turned off using the gpu for tracking and I have also flushed the cache. I’ve also played around with the amount of pixels to track, mesh generation method, mesh size, smoothness of track etc…But to no avail.

Do you guys have some ideas of what could be going wrong here? Any tips on what to try that I have not already done? I know that this should be trackable so I am at a loss for why Mocha is refusing to cooperate.

This is the version of Mocha that I am using:
Version 8.0.2 build 95.g5f0e592f5c34
Build Date Feb 16 2021

Any help is much appreciated.

I’d have to see it, there are too many variables to tell you what is going wrong without seeing what is happening.

thanks for your reply maryp.
As this is a real production shot for a film I am unable to provide any files or similar. But if I have the same issue with other non-commercial shots I will write on the forums again and ask. For now I had to ditch the mocha approach and use nuke’s smart vectors instead. Hopefully I will not have to do this in the future.

Ok. Next time I can always remote in if transferring files is not possible.