the LKQ is also a Mopar engine. It's just one that was re-assembled by someone else, with alot of used parts.
I called some of these rebuilders awhile back to ask about which brand lifters they use. Oddly, they wouldn't say, other than to repeat that the lifters were "tested", from one company and "proprietary, house brand" from another.

Make what you will of that, but I took it to mean that "tested" means 'used', and "house brand" to mean 'not Mopar'.
But, I understand. Of course, since it's still under warranty, you should absolutely go with the free warranty engine. I would too. But, I would keep expectations low.
I'm just curious, but did you got more miles out of your LKQ than were on the original OEM engine? Because, if I only go by your first post, the OEM engine was 9 years old (2014 to 2023), and the LKQ lasted what? From June of 2023 to now. So 2 years?
That brand new Mopar long block is $5k with free shipping. How much was the rebuilt LKQ engine?