If the shear pin was on the blade or blade mounting attachment I'd
agree with you. But this shear pin is on the flywheel, (located on
the top of the engine). Unless someone was to intentionally stick an
object thru the plastic cover over the flywheel, there is no reason
the flywheel will jam up. I do intend to get the correct part since I
need other parts anyhow, but I just can not understand why they have a
soft metal pin up there......

Well, you're looking at it because it sheared, right?
Which means that either the flywheel stopped when the
shaft didn't, or the other way around. DOesn't much
matter which.