What frame is popo's pummel cancel able with a throw?

[SecretAsianMan]

As a lot of you are probably aware, one of the desyncs the climbers can do is holding dash after a dashgrab, because nana keeps going for a bit, until she is out of the range of popo's directions then turns around and come back. A new desync combo I've been doing is dashgrab(hold dash) -> (wait for nana) down B(initiates dthrow) then up tilt for the up air string. I was wondering if I can pummel while nana does the blizzard for extra damage (mabe a bliztbobb from melee?) but it always initiates the dthrow. Is there any frame on the pummel that can't be interrupted?