BSB, I'm not the right person to answer this but I'll try. My understanding is that if the trial does end up having to repeat Phase III for any reason, then IMUC with their loaded antigen would move to the head of the FDA nGBM line. So in my eyes they'll be looking to avoid an error at all costs. And, since it's only an 8 month difference according to some here, then not halting and completing the trial seems to me the best way to go.
I can't answer with other examples, I don't know biotech well.