In this case it's related to Sammy's attack boxes, I will check it.
Just for curiosity. Usually I wait a little until enemies go down a bit in order to guarantee that all the default combo will hit. If you press buttons too quickly after putting an enemy into a knockdow state, certain characters with smaller body boxes will not take damage.
I can resize the attack boxes a bit to improve the collision, commonly I follow the sprite size but I can open an exception for this case.
Did some tests and confirmed that this is a minor path issue since the level background is based in the Abadede's ring.
But due to the new stadium level added recently, the Ring was renamed from st4d to st4e but I forgot to rename the paths for the Survival mode.
Thanks for the catch