It's very different.

JJ: You don't earn JJ points but "Multiplus points" instead. Think of multiplus as a huge rewards and loyalty system that tries to integrate and manage loyalty programmes for a bunch of different stuff. For example, fly a couple of segments with your LATAM Fidelidade number, earn points which are merged (outside and independently from TAM) with the rewards points you earn by shopping from groceries at your local supermarket, etc etc.
Afterwards, you can use points earned in all affiliated vendors on any affiliated vendor. You don't even need to be a TAM Fidelidade member to earn points as it is a much broader scheme.
Multiplus, which is part of the former TAM holding, is by itself worth as much as the airline.

LA: earn kms (besides from flying) by spending money on select retailers and hotels that have short or medium term co-branding partnerships with Latam Pass. All kms earning is handled by the airline. You cannot spend your kms outside of the airline (the catalog you linked to is, besides of limited, owned and operated by Latampass).

Both programmes may seem quite similar, but they are in fact very very different in the way they are run, the way they make a profit and the perks they offer, hence the difficulty in fully merging them