QC was going downhill the last year before Remington really took over.
Sending it to Marlin probably wasn't the best idea.
A known intermittent issue for years, if it's the same Marlin Jam. I've seen a Marlin actually disassembled at a CAS match to de-jam a stuck round.
It sometimes happened early in a newish gun, sometimes later with wear.
Depending on the timeframe, Marlin ignored it for a long time & then finally addressed it to a degree.
One of my wife's two .32-20s was doing it, we got a slightly re-designed part from Marlin that helped. That was about 8 or 9 years ago.
Gunsmiths familiar with them have done their own cures, you can Google to find them, I'd imagine.
Brockman in Idaho has worked on two of mine, part of that was to address the "problem" before (or in case) it ever developed.
My .44 has no cycling issues at all. It was bought for large animal defense & it HAS to work. Had a local guy go through the .357 years ago, no issues. None yet with a .45 Colt Marlin, but I'll probably ship it off for a going through just to be sure.
I'm not suggesting anybody avoid Marlins entirely, my .44 & the .45-70 are guns I'm betting my life on. They're not range toys & I do like Marlin leverguns.
You posted while I was typing.
IF Marlin fails, it'll be totally because of the product quality, NOT because of any "unfair finger pointing", and the public is not obligated to buy poorly built products just to keep an historical name afloat.
As I've repeatedly said- just inspect carefully before taking one home.