1.22b - Units covered in napalm aren't exploding

[WindStrike]

Just ran a match to see if I can get a pure fire tower out by 37 (it works, it's hilariously awesome), and towards the end of the game, I built some flamespewers. Something felt out of place when I had all these towers shooting and yet they weren't dying that fast when I noticed that units covered in the napalm were not exploding when dying. I don't know if this is the case of flamethrowers, but it is for flamespewers. I didn't combo with money towers, so that wasn't the case either.

Also, is napalm supposed to have a time limit on it? Right now, it just.. keeps on stacking with no falloff. Which I'm perfectly cool with it, just verifying that.

Here's the replay, it's at the end of it. Ran in VersusAI.

Flamespewer bug.SC2Replay