Hi Brandon,
Thank you for your answer!
Unfortunately, there are no such fields. hs_object_id I can see in HS API, but not in data coming from funnel.io.
There is one field called " Deal to contact json associations ", which contains JSON like “[{“toObjectId”: 194561522906, “associationTypes”: [{“category”: “HUBSPOT_DEFINED”, “typeId”: 4, “label”: null}]}]”, but It looks like LookerStudio doesn’t support JSON (only through RegExp, which I dont think will work with JOIN).