Been there with the splitting, it's so annoying when you're just trying to keep them alive in that heat. Glad yours sorted out once you backed off the water.

The part about not wanting to "kill the deal over a guess" is the thing that gets me, because that same thinking shows up everywhere, not just real estate. I see it with cars, with contractors, with doctors even. Someone gets told the honest thing and they grab onto the one cheap fix they heard about, and the person who knows better just steps back to keep the peace. The wet dog smell plus a foundation crack is not a guess though, that combo almost always means water is getting in and hydraulic cement is a band aid on a broken arm. You don't have to tell them walk away, but you can say the smell worries you more than the crack and they should get a real foundation guy in there before they fall in love with the place. Staying quiet isn't nice, it just moves the bad news down the road to the home inspector who they will trust more anyway.