Here is an idea for the mod to have Mordin live and cure genophage
When Shepard returns to Normandy after curing genophage, he receives an email from Wrex stating his team found Mordin badly injured near the Shroud and transferred him to hospital (Tuchanka or Sur'Kesh)
And for obvious reason his name won't be on the Normandy memorial wall and Garrus's dialog will change accordingly when Shepard interacts with him near the memorial wall after the mission.
Later, after 2 or more priority missions Mordin has recovered and joins the Crucible construction team.
Conditions: Mordin is loyal and Wrex is the clan leader.