IOTL, the English executed Joan of Arc in May 1431. The French did not lift a finger to save her(even though their king, Charles VII, owed his very throne to her). The challenge here is two-
fold:
1- Find someone- ANYONE- who you think would actually have wanted to save Joan; and-
2- Then figure out how they could have plucked Joan out of her prison @ Rouen & spirited her
away to safety