Yep, finding the right caramels and vanillas is a big part of a good ry4 type mix imo. I like both (original) TFA and FA Caramel but they're both coil gunkers. Not too bad used lightly in a ry4 type mix though. For vanilla, I really like a made up mix of TFA Vanilla Swirl, Vanilla Bean, and Vanillin.You just have to find the right caramel, after all caramel is just burnt sugar.
I would guess that it may be molasses without tasting it.