Multiple Salesforce records using same Box folder

I read through the previous posts but didn't see any specific solution for my issue:

I have customObjectA with normal embedded Box folders. This works fine. 

However, I have a related list of customObjectB that I need to share customObjectA's folder (I do not want separate folders for each customObjectB). 

I thought I could use createFolderAssociation() but apparently this only allows a single Salesforce record ID to be associated with any Box folder. Is there a way I can point multiple Salesforce records at the same Box folder?