I say he could dodge it. Why?
These are the advantages of being in toad sage mode:
1. The user's physical strength, speed, stamina, reflexes, and durability dramatically increase.
2. The user's ninjutsu, genjutsu, and taijutsu become more powerful.
3. The user can harness the natural energy surrounding them, turning it into an extension of their body, which increases the reach of their attacks.
4. The user gains the ability to sense chakra around them.
Jiraya has shown evidence of the first three advantages, so why not the fourth? It only makes sense that he'd have all the advantages even if it is imperfect.