Alpha Gallot saw the opportunity to sway Iris to his side, thus he thought why not give it a shot. Magic stones mine was a valuable asset after all. It would be a waste if Cane was unable to exploit the benefits of having one to the fullest.
He had tried to hint to him on the collaboration between them, where he could offer a platform for Cane to sell the stones, since the black market was located in his pack. Only, he didn't seem interested in the idea.
"If you want, I will help you to free your pack and be independent." Alpha Gallot could provide her with many warriors to take her pack back from Cane's hands.
More or less, he could read into the struggles that Cane had to face when he claimed the Blue Moon pack, or else he wouldn't have asked Alpha Gallot to veto his claim against the King's wish.