I'm personally not too concerned about a broken tile. My understanding is the underlayment is expected to have water on it and is the real protection.
I am concerned about penetrations into the underlayment. I hope those were done well. Looking at what they did with the flat roof penetrations looks good to me, so I'm hoping that means the tile roof penetrations were done well also.
My roofer has offered to come out and inspect the roof next week since I had both painters and solar installers on the roof. It will be interesting to hear what he says.
Not sure what your picture is showing. Is that gray material the underlayment?
On ours, the underlayment was a plastic on a rubberized glue-backed material. It is self-sealing for penetrations and had no drips even in rainstorms that occurred during the install. The embedded thunderstorms dropped 2 inches in a little over an hour.