Almost certainly not. We've seen Dave and John get dreamstabbed, and all it did was wake them up.
Well, I guess we technically don't know what it did to John, but Dave definitely woke up.
Right now, we have three kinds of dreambubble presences interacting. We have Jake, who's dreaming and should therefore just wake up when killed, we have Roxy, Dave, Rose, WV and the A2 trolls, who are physically in the bubbles and can probably die, and we have the A1 trolls. No idea what happens if they are killed.