@jn_7742 unfortunately, Microsoft has also abandoned Source Server in favor of SourceLink, and they will not add Source Server support to Portable PDB files
Technically, ProGet's Source Server works on Linux, but since ProGet can't inject its Source Server urls into the .pdb files, it's impractical to use. I'll let you guess which 20+ year old program is required to inject Source Server metadata into Microsoft PDB files
Bottom line, you'll need to upgrade your processes to use SourceLink