Right now, there are only five people registered for the jam, including me. How many are there normally?  

I won't be able to be in the same physical space due to being in another continent. Is that okay?

No, normally there are around 25+ people uploading games, most of them join itch.io late because it is not the primary source of information. Have a look at https://www.itec.aau.at/gamejam/ for more infos.

Regarding the location issue, I really don't know if it against the rules (will ask) - but I would highly recommend only joining if you plan on being a member on a team that is on location, even ask a few people on discord in advance if they want your help, because team building is usually done on location and nobody is gonna check itch.io for partners once the jam has started. If you wanted to create the game on your own, I'd suggest you try an online jam instead.