Hi @Jake_Olsby, sorry about the missing method in our client libraries—they tend to lag behind our official API due to the process involved in updating them with new features.
Unfortunately, we do not currently expose any mapping from a project to the portfolios it’s in—only from a portfolio to the projects it contains. Additionally, portfolios cannot be made public and must have an owner. This is a limitation of the web product that the API cannot avoid, but we will update the API as soon as we hear of changes to portfolios in the web product.