Just to be clear, it is possible to use any other cheap BT remote with Theta Z1 camera, like the one used by Yuqing Guo in his video, not only Joby or TR-1. The important thing is to make the pairing correctly.
yes, you can use other BT remotes. However, we do not know which ones work. If there is a video of Yuqing Guo using the remote, it likely will work for you too.
The only ones on the RICOH officially support list were the Joby or the TR-1, but other (not all) clickers appear to work. The best solution is to find clickers that other people have tested and then buy the same one.
I have a clicker that came with my selfie stick that doesn’t pair. However, I also have another one that does work.
I don’t recall having to pair the remote again. I have the Z1 and the Joby remote in a different office. I’ll try it again when I get back into the office.