I agree, take it out. I've seen this before where the chameleon ate the bark, became impacted and died. (Not my cham, someone elses.) Also he could damage his mouth on the bark.
You should get a new vet who is experienced with chameleons, since this one doesn't seem to know about them. He could have hurt or killed your chameleon. And that does sound like URI.
Yeah, pic 1 looks like a male based on the larger vent, and 2 seems to be a female due to the smaller vent. I'm just basing my opinions on vent, not color, because color can be misleading.