Here is my take, long long ago cams were different and many times on a cam swap if the old lifter slid out easy and the new one slid in easy I never had a problem.

Then everyone started mashing cams and getting nervous, so I started to set each lifter for each hole and it had to slide through on its own (many times a snug one will free up just by manually by hand with some lube cycling it up and down cleans things up) and then that lifter is good for that hole), then with the cam in and the weight of the pushrod spinning the cam gear by hand to verify all 16 move, it seems it takes little to get one hung up and not spinning.

I live in a good spot and hardly never shop break in a cam, its always a half hour of mild rpm, mild fun driving, just keep over 2k and let it vary.

But anyway,to me it kinda sounds like things were not happening in the rotation dept and like most posted, a fresh motor does best if it fires in the first three/five revolutions and its not hard to do although freaky to have a fresh motor fire so quick.

One thing to note is both your lifters look like many 340-s, even 318-s that ate cams, some of them were even worse and the lifter was very hard to remove.

Sucks though, hate to see it.