I'm not posting a video, but I managed to pull this off in training with the use of save states. Contender for the most difficult BB combo?
BB specific, 2 meter. Damage is irrelevant.
Jump-in, no CH, against a standing BB. Funnily enough, this is even harder (if not out-right impossible) against an initially airborne BB, despite the first four chains being all aerial attacks.
j.lp, j.mp, j.hp
j.lp, j.mp, j.hp
j.lp, j.mp, j.hp
j.lk, j.hp
s.hp
j.hk xx Timpani Drive
j.lk, LK Cymbals
j.mk x2, kara j.hp
c.lp x2, s.lk, c.mp x2, s.hk, HK "A" Train xx SSJ
This isn't intended for damage, but it's impossibly difficult to do. I don't know how many frames you have precisely, but you have to do three insanely hard chains in a row. j.lp, j.mp, j.hp is unbelievably difficult to pull off against BB, and it only works against BB because it whiffs on every other character. I'd estimate you have ~5 frames or so to get the timing right on j.mp, though it's probably either a lot more or a lot less than that. j.lp, j.mp is easy, but you need to do j.mp late enough that it won't whiff and early enough that j.hp won't whiff. Doing this three times in a row is extremely difficult.
After the third chain, things get a bit easier, but the timing's still pretty tight. The j.mk restand after LK cymbals from the top of the screen is fairly difficult to do on BB, but if it lands correctly then you're on the right track. After the kara j.hp land cancel into c.lp, the end of the combo should be muscle memory.
I don't really know what combocrafting like this is doing for me, but it's teaching me quite a bit about combos, so I may as well keep at it.
EDIT:
For gllt.
EDIT 2: Bonus 13k that's also extremely difficult:
CH 2 meter w/ charge
s.hk, HP Brass xx SSJ (Charged) (-100) [7630]
c.mp x2, s.hp (-50) [8070]
j.mk...x2, j.hp (0) [8610]
s.mk (20) [8730]
j.mp, j.mk...x2, j.hp (90) [9400]
j.lk, j.mk...x2, j.hp (155) [10060]
j.lp, j.mk...x2, j.hp (230) [10680]
c.lp...x2, s.lk, c.mp x2, s.hk, HK "A" Train xx SSJ (330) [12917]