Just refer the Bidens for prosecution. If Garland won’t, impeach him. Repeat.
Impeaching Garland would take a backbone. Most Republicans are furthering their careers and getting richer; they don’t want the negative press. They won’t impeach anyone.
If the full court of SCOTUS was to select and assign the special council, then fine.
Picking which fox will be in charge of guarding the hen house is a no-win situation. They’re all light years beyond corrupt in the current party in charge of the Senate and executive branch.