Plus Peregrine said in the lawsuit materials that people have posted from PACER that swapping occured in both arms, so how could the 3mg not be tainted?
As was pointed out the 3mg arm was not tainted, but the placebo arm was. So instead of having a clean placebo arm to compare against the 3mg arm, they had to pool the placebo arm and 1mg arm data to use as a comparator. Against that pooled data, the benefit of the 3mg arm did not reach stat sig. So no AA.
The result is by comparison of the 3mg/kg arm with the control arm and therefore the FDA had to take this position. And the 3mg/kg ALONE wasn't stat sig.
So at least they needed confirmation to avoid all kinds of trouble and/or possible complaints later.