New tristana and her E's interaction with untargetable spells

So, I was playing a Vladimir one game against a Tristana mid, and we agreed to test what happens if 1) I pool right before Tristana's bomb lands on me, and 2) I pool after Tristana's bomb is already on me and about to explode.

I found this:

1. The bomb explodes instantly. No animation, but instant damage. The damage applied right after I pooled before it landed.
2. The bomb does nothing and shows no animation when it explodes.

The second one seems to be working as intended(I have no idea what Riot intends, so yeah), but the first one seems to be a bug. I would like some clarification from Riot if this is intentional or not, as this may affect the gameplay for both parties, positively or negatively on either side. Unfortunately, someone else will have to test this out with Fizz if they are curious about that, too, as I don't own him.