In case anyone else has this problem, here's where I found what I needed.
Methods: buildCategoryBreadcrumbs and buildBreadcrumbs
Editing those allowed me to get the behavior I was looking for. Although, I would be curious to know if there is a better way to do this without changing the source code.
@gorgiselkov I believe that one might not be working because it's a skeleton plugin, and not an actual SSO auth (as stated on github page), unless you've configured it yourself but, it doesn't seem like it.