The Combo:
In corner - 2AAA, 6C, 4C, 2C, delay 5C (wallslam 1), 2C, 2A(whiff), {5A, 2C, 2A(whiff)}repeat x3 -> 2A, 2C, delay 5C(wallslam 2), {5A, 2C, 2A(whiff)}repeat x2, 2A, 2C, (two options at this point)*
*option A: Flame Pit Setup = 623B, tk.22C
*option B: Extra Damage Setup = charged 5BB, air combo.
Apparently, timing is extremely tight. 2C -> 5C needs about 18 frames of delay (that number seems huge but in training mode what i did was 2[C] -> 5C then i look at the input, see how long i held the button after pressing it again for 5C. this is roughly before the character hits the ground) after 2C before hitting 5C so the next 2C would connect. the 5C delay on the second wallslam is shorter but the hit occurs on the opponents same animation frame as the first wallslam.
Going from 5A to 2C can get extremely difficult, if you hit 5A too early, it will connect however, 2C will never come out. Hit 5A too late, and they tech or you miss, hit 5A just right and 2C will combo just fine.
I still have a really hard time nailing the combo properly, I can get a good amount of reps but the timing is just hard. Timing can also be character specific, the timing is much more tight against Hisui than it is against Warachia.
If I made any mistakes, please say so and I'll try to fix it immediately. Oh and... Discuss!
EDIT: made some fixes and added a bit more detail