So at the moment Streamlabs does not have this listener on their documentation, but the dev for streamlabs informed me in an email that there is an event type for Streamlabs Charity donations called streamlabscharitydonation. I haven't been able to test it myself since I'm not very knowledgeable with Java applications, but I assume this could easily be added if it does work so that the mod can support Charity donations as well through Streamlabs.

Hey there!

Unfortunately @stream-labs Docs has an outdated information on which events are being emitted over their Socket API. 😞

However, if you could provide me a log from a TwitchSpawn session, where you receive a Streamlabs Charity Donation event, I could try to reverse engineer the data shape out of it! 🎉

The docs link mentioned above:
https://dev.streamlabs.com/docs/socket-api