I tried in Bitwig 5.2.7 and 5.3 Beta 3, and had the same issue.
GR7 is not showing in my plugin browser, so I found the vst3 file through the file browser in Bitwig and tried open it, but ended up with an error popping up. (Screenshot attached) I can't understand what the error mean, but maybe it's because my system language is in japanese??
In fact, I had GR6 and GR6 worked normally without this kind of issue. However, after I installed GR7, I uninstalled GR6. Then after I found I can't open GR7, I reinstalled GR6. But this time, GR6 had the same issue with GR7 (not showing in browser, same error popping up).
I tried in Cubase 13, but it all worked normally without this issue.
Not sure whether it's Bitwig issue or plugin's fault, can anyone help me?