Y->Y->Change Direction->B
Nope, B-reversed DJC PKF would be Y->Y->SideB->opposite direction (within 4 frames). B-Reversing is the act of reversing the direction of your special
after it was initiated resulting in a complete momentum reversal. It allows some pretty funny movement with DJC PKFs like jumping in one direction, double jumping in the other and then B-reversing a late PKF.
If you reverse your special before activating it, your momentum is unaffected - that's what would happen with the inputs you suggested. I believe that would be called a B-Turnaround, but don't quote me on this.
I've got a question about DJC Aerials. Quickly moving to the c-stick is pretty challenging and I find c down to be the easiest. Often times I have trouble doing c forward when moving that quickly to the c stick and I accidently an angle closer to down which causes a dair instead of fair. How do you guys get fairs in quicker?
I just claw everything.

If you don't want to do that (most people don't), there still are different tricks that might help you.
Custom controls is one way. The control scheme I have heard of most often is setting Z to jump and using any of R/L+A, X/Y, R/L for grabs. The second to last post right now in the general discussion thread actually recommends doing this and apparently it makes many things much easier once you're comfortable with the new controls. Relearning the control scheme is strange at first and takes some time, but if you intend to ever optimize your controls for easier gameplay, you should do it as soon as possible, i.e. now.
If you also don't want to do that you can try to operate the C-stick with the lower part of your thump. Neon does something like this (see above). Requires less relearning of controls, but feels the most straining to me personally. Might just be a matter of preference though.
Finally, should nothing else work for you, you can also just train more. It'll take a while, but if you just keep practicing your ATs every day, you'll get fast enough eventually.