Even the Land of Earth Daimyo understood Ōnoki's desire to preserve his strength and wait for the right moment. But to say he held no resentment toward Iwagakure whatsoever would definitely be nonsense.
Leaving aside everything else, the Land of Earth was now under attack from two sides. Aside from geographical factors, Ōnoki's own tendency to abandon principles for profit and deeply offend the two major shinobi villages was certainly another major reason.
At a time like this, after learning that Konoha wanted to station shinobi forces in the Land of Earth—specifically in territory occupied by Kumogakure—the Land of Earth Daimyo naturally could not refuse.
Very soon, the shinobi sent to the Land of Earth returned with the Land of Earth Daimyo's contract. It permitted Konoha Village to station three thousand shinobi in the Land of Earth, accept and carry out missions there, and receive the same treatment as Iwagakure for the funding of its stationed forces.
This negotiation had been personally handled by Konoha's Yellow Flash, Namikaze Minato. Aside from the incredible speed of his Flying Thunder God Technique, his sunny, little-sun-like image also greatly helped his negotiations. Coupled with Minato's intelligence, caution, and outstanding big picture thinking, he was the ideal choice for the job.
And Minato did not disappoint. He brought back the contract in just three days. At that time, the Third Hokage was still playing diplomatic games with Kitsuchi.
The moment the contract was in hand, the Third Hokage immediately agreed to Kitsuchi's request for aid. Konoha had long since reached an agreement with the Land of Earth Daimyo anyway, and now it could also fleece Iwagakure for a sum. Why not?
Kitsuchi had thought it was his sincerity and the terms Iwagakure offered that had moved the Third Hokage. He had been so touched