Are you ignoring the PJ who after all have primacy over the investigation.
Yes.
My understanding of the PJ involvement is that it consists of 2 parts. The first is the effort in Oporto. I know only a little about this, but its focus seems to be outside Portugal. The second is the effort on the Algarve, which despite the primacy quote is merely a unit to handle legitimate requests emanating from Operation Grange.
If I went to the PJ I would get hauled down to Portimão or Faro for a day in their company. This would be the excruciating routine of questions in Portuguese, translated into English, response in English and typed up in Portuguese.
Then what would happen to the information? At best, it would get sent to OG, which I have already done. At worst, it would get sent to Oporto, upon which I could get hauled to either Faro or Oporto. Such jolly times.
And then when the case gets archived, my personal and contact details will get revealed for every aspiring journalist to see.
The information has already been communicated to the UK team. I will not get invited to Belgravia. And my personal details will not ever become public.