Found this in my left hand wiper well, below the cowl vents.

Cant tell the size but looks like a front upper shock washer.Rocky

looks like the rubber to a hood adjuster on the coner of core supports.

slips over the flat head of the adjuster bolt.

but pics are tricky sometimes.

I guess another pic might not hurt.
This is the other side.
It is approx 1-1 1/2 in diameter.
I would be awful odd if it came from e anywhere but the wiper motor linkage, because the area is enclosed that I found it in.
But I don't see anything obvious.

Isn't there a rubber "boot" that seals where the shaft comes out of the wiper motor?

Well it is not a rubber bumper, and yes the boot is on the wiper linkage, BUT is something supposed to cover the area mating the motor to the sheet metal?
It is strange because the wiper linkage has not been messed with as far as I know of.
BTW this part is only like 3/8 thick but not solid, more accordion style.

Carpet dimmer switch grommet

Looks very similar to the dimmer switch grommet, but hole is much smaller. I guess I may never figure it out. I just assumed it went to the wiper linkage somehow.