Yes! AMA doc 510-A number 22 states: "All Pilots operating turbine powered model aircraft solo shall have a qualifying waiver affidavit on file with the AMA." In your case - taxi tests, ie to check the brakes, run up the turbine etc - cannot be done at an AMA field unless another turbine waivered pilot is around / at the controls.

This protects the AMA against someone "operating" a turbine at an AMA sanctioned field and causing damage/harm by some means who is not waivered. At that point the AMA's insurance would not be valid.

So I'd say you need to find a waivered turbine pilot and have him help you out, which is a good thing to do. Or go to a suitable site that is not an AMA sanctioned flying field.

JR