I think it will hurt Israel that Iran is gaining so much from this MOU/deal. They will definitely try to disrupt this deal by continuing to occupy southern Lebanon (they might not kill as many people, but might only continue their occupation to provoke Hezbollah to attack them first, and for them to retaliate to those attacks).
But without US backing, Israel’s long term security will be further diminished.
If I were the Iranian regime, I would want this deal to go through and continue. I would want Iran to restrengthen economically, militarily; clandestinely support Hezbollah in Lebanon (which they are still able to do, the FPV drones are proof of that).
When Israel commits further killings over the next few days/weeks, keep warning the US that they are being patient, but the Israelis are undermining Trump’s deal, and they’ll be forced to retaliate.
I think Hezbollah has enough strength and firepower to handle the Israeli land incursions for some time at least.
Residents of southern Lebanon need to return and reclaim their territory, and make the occupation as difficult for the Israelis as possible.