The Cloth simulation time step smoothing is interfering with the substepping fix for multi Temporal Samples by changing the very variable DeltaTime and causing some large errors in the cloth simulation due to increasing/decreasing convergence.
Simulating with p.ChaosCloth.UseTimeStepSmoothing 0 fixes the issue.
This Cvar needs to be added to the MovieRenderPipeline startup sequence to solve this issue for everyone.
Actual result: The cloth simulate with weird undulating jitters.
Expected result: The cloth simulate without jitters.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-172069 in the post.