@NoHoldsBarred thank you very much for sharing your logs. We will investigate this asap.
As a near-term workaround you can try the steps I posted here to get unblocked. https://forums.unrealengine.com/t/failed-to-load-fragment-payload-for/2621582/2?u=gxg_work
A note for this workaround: upon your first check-in after performing it, please carefully review the changes that appear in the submit dialog and right-click–>revert any changes you do not recognize.
While regenerating the URC folder helps work around issues like this, it means the context is lost on the last snapshot you had synced, so it is easy to push forward older states of files that your collaborators have since changed, overwriting their work unless you dig for it in the snapshot history.