Hah sorry, I should've thought of that. Long story short: This instance is running on latest Lemmy beta version. Lemmy made a recent change to the beta version which breaks 3rd party apps like Jerboa. DO tried to rollback their version but it failed. We now have to wait until the 3rd party apps release an update that works with Lemmy beta(or future v0.19 when released).
The most recent update from instance owners saying the same thing:
After some additional digging through the Lemmy diff for beta.5 to beta.8 (and then looking through the PRs that were merged to create this diff), the issue is indeed with the Lemmy code and is even called out in one of the PRs,. What this means is that the 3rd party clients that are not able to access the site will need to update their code to fix things on their side (or else they will be broken when v0.19 is released and all other instances update to it).