Hey ambi, don´t know if you´ve updated the 2.8 addon in the last two days or so but I had some issues with it when i tried it on friday.
The issue appeared when remeshing an object containing two or more meshes. your call to triangulate the bmesh uses the numeric syntax (ex ngon_method=0) which doesn´t seem to be supported anymore, switched them to ngon_method=‘BEAUTY’ or something like that (not at home right now). Which solved the issue.
I also played around with making the remesher usable from sculpt-mode. Since you apply the scale before running the vdb-operations you have to switch to object-mode. So I just checked if i were in sculpt-mode before doing anything, then switched to object mode, let your code do the magic, and then switched back to sculpt-mode if it was called from sculpt-mode. something to consider! If not it´s an easy small operator for me to write a hack around your code
Awesome to see the addon in 2.8, keep up the good work!