Snakepit doesn't seem to apply to Blazing Salvo (Runegraft of Recompense)

I made a video going over this that I'll link below. The skills says it gains 1 chain, but it doesn't return any mana when it ends. When testing with touch of anguish as the only source of chain, it does return mana.

https://www.youtube.com/watch?v=AUuELjtcFE4

I am experiencing the same issue with different skills. It appears that the "projectiles chain" wording is functioning differently from the "skills chain" wording.

Chain Support or Roth's Reach chains will refund mana w/ Eye of Winter, but chains from Snakepit or Replica Voidwalker will not.