That must be an odd situation with vibrations and resonance of your aircraft. The normal advice is usually the correct way of doing things. It would definitely be acceptable to lower the gyro value if experiencing issues, of course.
I’m glad you got a solution, always good to hear about more non-retail aircraft in the air.
Edit:
The PSC_ACCZ params are fine at defaults, usually best using the formulas, but also OK to go with whatever works. Smaller overpowered quads generally need PSC_ACCZ values well outside the normal range.
For the Gyro and related filter settings if the calculated values give less than ideal results, go with a some basic ranges like 40/20 , 30/15 or 20/10 , working your way lower until there’s stability.