I was actually practicing this and I think it'll all connect if you use BK. Also, if it's in a corner... you don't need to dash and 5B > 6A, 6A will usually work.
(BK active) 5B > 6A > 5C > 5D(1) > 214B > (no delay)214D > 665B > 6A > hjc > air combo
(corner, BK active) 5B > 6A > 5C > 5D(1) > 214B > (no delay)214D > 6A > hjc > air combo
Might have to test further on others. Haven't had a lot of luck without BK for the followup after 214D. Unless of course you want to RC.