My hibiscus is under attack.

Although it's 5-6' high, it's in a tough location for a hibiscus, growing partially under a 20' high bougainvillea in a corner of the yard. The bougainvillea and fence make for a semi-shaded alcove that doesn't get much breeze. The covered half of the bush developed an infestation of white flies and their nasty white fungal-looking streamers that grew under many leaves. I'm treating that with neem & soap spray & pruning.

This posting is about a worm-like bug that I found on a branch. The grey bug spits (or poops?) every 3-5 seconds - grosss. A couple evenings ago, I found 3 of them on different branches. The branches didn't look damaged but that bush gets a lot of bugs due to its location (spiders love it too)

Here's a photo. Are those antenna on the bottom-left?

Here's a 3 second movie which is hard to see in the small version here; it's somewhat better when viewed in full-size on YouTube itself:

Does anybody know what that bug is?

Any suggestions for treatment?