Ok, figured it out.
For those in similar cases, you MUST first search the community in the search bar here. Searching !golang@lemmy.ml only returned this thread initially, but after a few seconds the community appears in the search results.
From there, the community will sync here and will be visible here, with new posts appearing over time (afaik it doesn't sync existing posts, only new ones).
Hope this clears up the process for the next persons in my position :)