Oh, I think we have a lot of clues.. you just need to open your eyes (or mind).
For example, there are some very big players chasing P2O technologies today, including well-known silicon valley VCs, WasteManagement Inc, Dow Chemical, private equity firms, etc. So if these people believe P2O can overall be viable (whether it's Agilyx, Cynar, NillTech, or Splainex...) then JBI has at least as good a chance. I say "at least" because as has been pointed out here hundreds of times before, JBI's technology seems to be superior in many (or every) respect: capex costs, automation & safety, efficiency, fuel quality output, feedstock tolerance, physical footprint, etc.
These are the "clues" as to whether Plastic2Oil® will be profitable, and they are all around you.