Are there gender neutral bathrooms available at the convention center?

No.

I think it depends on the event

I was there for three days in February 2018, and the answer is no.

Not quite sure.

I didn't recall seeing any last time there, I doubt that they have room to add any or convert any current ones.

Didn't see anything like that

Thankfully, none that i have noticed.

I didn't notice one there, only a mens and a womens.