Yes, I have let go of the idea of finding the source of the pins. I've operated the saw without a blade (and without a lot of the parts, like covers, scales, dials, tables, etc) and have thus far observed nothing unusual in terms of sound or vibration.
I have physically located, looked at, and lubricated each and every one of the stop pins as identified in every figure of the parts explosion diagram, and have inventoried every stop position in bevel tilt rotation, rip turret rotation, miter swing swivel, and carriage travel, and all pins are not only present and accounted for, but they are each remarkably different than the two twin mysterious pins that magically appeared on the floor and table of my RAS during the last use.
I'm OK with redeployment of the RAS. Right now, I'm working on optimal reassembly, researching the archives of this forum for threads relevant to radial saws. Please don't be surprised if you see some fresh dirt piles pop up in the forum cemetery.