I'm not absolutely sure what type of blasting media it was but there are full, clear beads in the oil filter shell about 1mm in diameter. There are also remnants of the blasting media all throughout the engine and clearly in the oil pan and draining back onto the metal plate of the oil pan from above, presumably crushed from the oil pump. See the two images below.
I know the beads didn't make their way into the bearings since they weren't scoured, but what I do know is that the oil channels were blocked such that the whole short block toasted itself so bad that the block is unusable.
So, what I was trying to do with a vacuum tester is get an idea how much pressure (negative in this case) would it take to draw the crushed blasting media and oil mixture thru a hole the same size as the oil delivery passages. I know the bypass valve pressure of the oil filter and I know the filter had crushed media in it, so if the filter was clogged and the bypass opened then the slurry of crushed media and oil made it's way into the oiling system. On a cold start (10*F) I know the viscosity was quite high and that's when the oil light came on and then the engine went kaboom!
So yeah, the vacuum test isn't perfect, but in small claims the judge may want some pressure data. I'd rather be more prepared than not.