I am surfacing some messy geo and used a VDB surfacing approach. Are there better ways to achieve this or a different approach that has proven well in practice?

Here is my approach:

try to fill some of those holes first, use polyFill etc

and I think the mesh needs to be reversed also

HTH

You may want to look into the vdb reshape node and set the operation to "close".
Alternatively, after scattering points onto the surface the point cloud surface node could also be helpful.