CantCompeteWithUs
Member
If you remember on the beginning of his mission while he was infiltrating the rain village that he hid inside of his toad. My thinking is that he could have used that very same technique as he was drowning to what we thought was his death. Being inside of Gamubunta he is "busy" as of what Gamakitchi said. That is the reason he wasn't the one summoned because no summoning monster can ignore when they are being called out to the battlefield. Just like when Naruto first was learning how to perform the summoning jutsu when he was thrown into that trench and summoned Gamubunta. He couldn't ignore it and was summoned forcingly