Do those PI Servers form a PI Server Collective?
Are tags serviced by PI Interfaces?
Is PI Buffer Subsystem in place and set up for n-way buffering or what mechanism is used for data replication?
The fact that you see the issue on the first PI Server but not on the second one indicates a data flow from the second PI Server to the first one. Is this correct?
I am also a little bit in doubt about the timestamps that differ a lot between both servers. Did you retrieve the data on the same client and if so relative to server or client time?
Instead of disabling compression, we recommend to enable it and set compdevpercent to 0. There's no value in storing the same value again and again if it doesn't change.