For the sake of the challenge, it still counts as a death.
Umm... That doesn't really seem fair, because you don't actually die, and the goal of the survival challenge is to survive, right? So, it doesn't seem right for a deathbomb (which keeps you alive) to add 1 to both your death count and bomb count... (And if you manage to deathbomb a lot, you could end up with a death count that's much higher than the number of lives you could possibly have in the game, which is kind of ridiculous.)
How about this: In addition to the final stats screen, we could take a screenshot at the point where the final end-of-stage bonuses are displayed as well, and then figure out the number of deaths from the lives remaining at that point. If a player gets all of the score-based 1-ups and both 1-up drops from the stage 3 and 5 midbosses, and doesn't die, that player will have the maximum of 8 reserve lives at the end of the game. (I guess we could consider letting a 1-up item drop count as a death if you decide to go that way, unless the final stats screen shows 0 misses to disprove any possible deaths.)
Oh, but the player could start with more than the default amount of lives to throw that off, but maybe the challenge could require that the player start with the default number of lives, which could be verified by looking at the very start of the replay.
What do you think of those ideas?
(Man, why did this challenge have to be complicated by that previously unimportant death counter glitch in EoSD?)