Am confused, did have any roots on the bottom of the cutting when you potted it up?

Yes, it had about 4-6 inches of root

I don't see any of that in your pix. I pot mine up w/ just 1 or 2 inches of roots. Don't know how it would do w/ such long roots (or why do it like that).

I tend to pot up shorter lengths of these plants, just 6 inch cuttings w/ an inch or 2 of roots. Unless I'm misunderstanding, are you trying to pot up long lengths of cuttings? As long as the 2nd pic?

The cutting is about a foot long. I potted it into soil a few days ago so the roots aren’t visible. I normally do it much sooner, but my grandma lets them grow you months/years in water because she forgets about them. I have no clue how long the cutting was in water before I got it. The longer one was just an example of a healthy cutting from the same plant.

I'm sorry, this is too confusing for me to follow. You've repeated you don't know how long it was rooting. I don't know that it matters.

Perhaps where I should have started was you might have left it in the pot for a week even if it has a couple of leaves yellowing, for it to adapt to its new situation, perhaps it's some transplant shock. It's not going to settle in overnight, unrealistic to think it would.

Apologies if I'm misunderstanding.

If mine, I'd cut the long vines into 6" lengths, snip the bottom inch off w/ any of its roots & place them in a 1/2 cup of water to re-root all over again. Then, when the new roots are an inch long, I'd pot them up in a small pot. A good ratio could be like 3 cuttings per 3 inch pot & allow a few days for them to adapt.