free accelerate thru viabtc or confirmtx won't work, way off their requirements
if it was 10+sats/byte might have greater chance to get confirmed
the only way you can do right now probably by trying double spend it
but looking at the size, you would better send them in batches (or consolidate them first)
I'm not quite sure about this but it seems with same low fee rate,
smaller size txs get confirmed a lot faster than those bigger size txs