Here's the update. I was there this morning (I help set up chairs), and the "new" band starts showing up. I was talking with the drummer, who doesn't know me, he said they were putting together a new band, and were starting practice at 10:00. I got to working on the bass. What a MESS! The G saddle was not only missing a screw, and bottoming out, but the one saddle screw there was had been mounted upside down. I found the same thing true about two other string saddle screws. I fixed all but one for lack of time. The spare bridge I had was fine thread, and I think his MIM Jazz has coarse, so I simply swapped out one whole saddle assembly. I set it up as best I could in 5 minutes, and did a quick intonation.
When I left around 10:30, the bass player still hadn't showed up, and they were practicing for tomorrow's service without him. The last time he played, he was out in the parking lot when the band came back up to play after the sermon. I sense a pattern. I don't know this kid, and I'm sure he's good guy, but he's obviously not focused on the times when he's asked to play.