Results from developing 1940s (?) film in sealed P Charger, Part 1

I bought this sealed charger off Etsy this week. The seller obviously had no idea of age or condition of the film inside, but I thought it was such an exciting idea to try to develop whatever was in it that I took a chance at £20 +£2 postage.

It's a P style charger, and I read that these were introduced in 1927 and superseded by the H charger in 1937. The film could be much later than that of course, but it could easily be from, say, the 1940s.
It was very hard to open it, (yes, in the dark ;-) even after the seal was broken and inside was a very full chamber of film. In fact it was so packed with film it was difficult to actually get any out.  I clipped off 2 sections and developed one in stock Perceptol and the other in coffee (Caffenol C-M) with iodised salt to address fogging. I've had success developing glass plates from the 1920s in coffee so it seemed a  good place to start.

The results: oh dear.  I try to be brave but  little bit of me when I pull out a failed piece of film from the fixer.

The Perceptol clip had no sign of any images, just blotchy thick dark fog. The Caffenol clip looked the same, but looking closer, there seemed to be vague shapes in some areas, so I developed another section, and this time there are faint images to be seen.  I don't know if it's negative film which would be turned positive during development, or reversal film but here it is reversed:

I'll be experimenting further with different developers and methods but it seems reasonable to hope there are better images to be had from this. It would be a cruel trick of the Universe if these few frames are the best from 50+ feet!

I'll update here as improved results appear, but for now here's the best frame of the lot. Intriguing...