Alright, if someone is still interested, i just rewrote the Jitsi Nextcloud Talk bot in Go, which should make everything much faster and simpler to deploy: https://github.com/pojntfx/nextcloud-talk-jitsi-bot
I even did a short video (in German) explaining the usage: https://www.youtube.com/watch?v=ahwGVSfwssM
Maybe this could be a good intermediary solution; if you want to build your own chatbots etc., the Nextcloud Talk Jitsi Bot provides a simple framework to do so if you know Golang.