Nope, never heard of that happening before either and we been doing this for MANY , MANY years. Yes, back in the early 50's, the "two piece" Korean War vintage made bolts, had a "pressed on" piece , that had tapered wings. This was due to the company using 1-inch bar stock to make the bolts, , instead of machining the entire bolt down from a 2-inch piece, this "saved" steel for the war effort. Anyway, these two piece early bolts were 'prone' to loosen and posibbly shot off, so were recalled and replaced at the factory back then. They did this as a matter of 'policy' when they came across one, they just "replaced/updated" the gun, drew little of no attention to this "problem".
As I said, I don't recall this ever happening 'later' on in the MK I's or the MK II's either. I have a couple of bolts setting here and they are definitely ,solid, all one piece and even then the face of the bolt is what 'hit's the inside of the frame (barrel end) so the 'wings' (ears) should NOT ever take any beating or abuse. Thus I'd had to say something is 'defective' and certainly covered by their warranty.
As said above call them and you'd only have to send in the bolt, NOT the entire gun I'd speculate.