here's a link that may help, I am using a similar method to post to lemmy from calckey.

@cafe@monyet.cc

unfortunately, it seems a feature request to add microblogging functionality to lemmy was rejected by the devs: https://github.com/LemmyNet/lemmy/issues/3402

based on what she mentioned here, most likely not

@dukeGR4@monyet.cc using an instance of the rimgo alt frontend, the url becomes: https://rimgo.kling.gg/a/F3i13pF

nice and lightweight, no js required 🆒 #altfrontends

@cendawanita@monyet.cc @cafe@monyet.cc and it works, yay 🎉🤯

edit: thanks for your long and informative post. by the way, when talking about calckey, you said "another german dude", who's the first german dude to go up against mastodon?

@cendawanita@monyet.cc @cafe@monyet.cc testing from calckey 14.0.0-dev46

so far, to make this work I've had to:

1. pick a calckey instance that's running a pre-release of the latest version 14
2. made sure it was already on https://monyet.cc/instances to increase the chances of federation working
3. search for the /c/cafe community first, and made sure the follow request completed successfully
4. and only then, search for your post, and reply to it, tagging/mentioning the community too

probably some of the steps are not needed, but I just wanted to throw everything that would increase the chances of it working at my attempt 😆