The knives in the middle don't have a name because I'm fairly certain that they were never released. The Escalator model was produced toward the end of REKAT's existence, which is why you don't find very many of them. Those Escalator trainers are even harder to come by.
It appears to me that REKAT was experimenting with the idea of putting Pioneer-style drop-point and tanto blades on Escalator handles and you managed to acquire some of the prototypes. I've never seen them before, and I thought I'd seen every REKAT model out there!
Not all REKAT blades were coated. The earliest blades came with a polished/brushed finish (with black coating as an option), and REKAT also offered a stonewashed finish on some later models. Colored G-10 appeared rarely, but it was used; there was a red-handled Blade Forums special edition of the Sifu, and I recall a red-handled Pikuni, as well. I've never seen a white G-10 model.
You have some remarkably rare knives there and I thank you for sharing the photo. I'm not trying to pry, but I would be very interested in learning how you acquired them as a group. Did you buy them from someone who had an affiliation with REKAT?
-Steve