So, I noticed his entire twitter, patreon and Pixiv has been nuked as if they never existed in the first place and I can’t seem to find him anywhere. His art (at least some of it) still remains here so I’m not sure what is happening here.

Does anyone know what is going on with this artist?

sounds like they decided to either up and leave the art scene, or migrate without announcing to start a new.

seems that this is still active, according to the links in their artist wiki
https://twitter.com/dsoan36 possible migration

Not sure this helps at all, but seems that their Patreon was shut down on June 30

I guess we can only wait and see how things progress, hopefully the artist will return one day.