[GAMEPLAY] Dragon "assist" only giving devourer 1 stack

Just tried this out in a custom game with 1 ally. The first time we killed dragon (while I had devourer) he got the last hit on it and I did not get any stacks on my devourer.

Figuring this may have been just a bug with us waiting too long between me not hitting it and him last hitting it we tried a second time with him "smite stealing" it from me (we were both on the same team and we each had smite). On the second attempt it only gave 1 devourer stack.