I read through and didn’t see a mention of what power meter you’re using for power match. If you’re using the favero assioma pedals (left pedal version), be aware that a recent firmware update caused the pedal to only report half the power output to your computer/phone (i.e. it didn’t double the left pedal’s power before sending it to your device).
If this is the case for you, you can open a support ticket with favero and they’ll send you a new firmware update that fixes the problem. This drove me insane when it first happened and I couldn’t figure out why my warmups were so hard.
As an aside, I too have had problems with the kickr snap power accuracy. With power match off, the kickr is continuously 20-40 watts harder than every other power meter I’ve used (favero pedals, stages crank arm, etc.).