It's a miracle those nurses didn't sever his jugular vein while they were hacking away!
They made two small overlapping slits below the inner collar band and a slight nick on the top of the tie.
I take it you're just going to keep avoiding the fact that there was no hole through the tie? This a textbook case of self-delusion and an ability to face disturbing fact.
If a bullet had exited the shirt slits, it would have to had to tear through the tie. It could not have missed the tie. It would have torn a hole through the bottom part of the tie knot. But there is no hole through the tie. There is only a small nick on top of the tie knot near the left edge of the knot. Obviously, no bullet could have exited the slits and then magically weaved around the body of the knot and nicked the top of the knot. At least not on this planet and not in this reality.
The FBI knew this. This is why the FBI fought so doggedly, for 10 years, to avoid releasing their photos of the tie.