Just so you know that 9 member number is not at all accurate. Not sure how kbin handles it but it's likely that's closer to 9 members from your instance. Best way to get a true count is to check on the original instance. Currently showing 208 members which is actually TWICE what it was a week ago. I believe this is primarily due to my promotion posts:
https://lemmy.blahaj.zone/post/1102558?scrollToComments=true
https://lemmy.blahaj.zone/post/1072700?scrollToComments=true
I think that the fact that I was able to double the number of subscribers of a largely inactive sub demonstrates that there's enough people looking for this exact thing to sustain a community. My legitimate recommendation to you is to simply post. I think at this point discussion would probably get the most engagement. Also don't forget to crosspost. Crossposting is an important way to introduce new people to growing communities. If you're completely uninterested in posting I suggest you make some noise over on beehaw. One of the mods over there responded to my post by saying it was something they had been looking into. https://beehaw.org/comment/722094
EDIT: Edited to say that community has not really gotten any major wave of activity since the migration. I think regular posts would very quickly grow the community.