While testing is always an elevated risk, this does not yet appear to be test related
Gathering baseline data is test related. Ideally, following the installation of the test article on the airplane, the test flying and comparison to baseline data, shows no change, or desired improvement. But, it should be that no maneuver is being flown with the test article installed, which was not first flown baseline. When I flew a Caravan spin program, I very certainly spun the basic airplane first, just to get used to handling and recovery techniques. That done, any difference with the test article installed was a delta to the base airplane, rather than a whole new unknown. And, if an airplane is edging on non compliant in the basic configuration, it's useful to know that before installing the test article, lest the test article be incorrectly thought to be the reason for an observed non compliance. I have certainly flown baseline, then modified, found something unexpected, and had the mod removed to fly more baseline, just to compare.