“What are you isolating by this?”
Removal of the holder being able to have an influence on the results.
There is not way to scientifically prove that you had no knowledge of what the results would / should be. If this is a real effect that is not caused by any influence of the holder it will still happen in a double blind test. If you really want to know if the effect is real and not caused in any way by you holding the pendulum this is the gold standard of proving it.
“This entire conversation has been a shit show and it’s because you don’t know how to investigate something respectfully.”
I could say the same about you refusing to accept challenges to your methodology.