Formula URL to Add Records with a Reference Proxy Field

I have a table with lookup fields to related tables. Only one lookup field is required to be populated when adding a record, and that field has a drop down menu made up of a report link to a related table. I can api_addrecord to actually populate the necessary fields except, when I look at the new record, the lookup field is blank and the related fields didn't populate. When I choose to edit the record, the lookup fields immediately populate but I still have to select the drop down value.

Is it possible to make a formula url that will lead to the lookup fields being populated after the call? Also, how do I populate the lookup field with the formul url? Is it even possible?