Can I get a Replacement?

Dawe Universal press camera taken with a Minolta Miniflex 4x4 TLR on Agfa Superpan Supreme.

I bought an odd roll of 127 film for 50p from Doug Palmer's lovely shop in Bridport a few weeks ago. Needing to try out a new (old) camera, I unwrapped it and found myself with a roll of Agfa Superpan Supreme, no less, which from what I can gather would have been made during World War 2. I peeled off the tape and found this little notice, which clearly says that if I am not fully satisfied I can send the negatives to a New York address for a free replacement roll. I reckon that at the time of exposure it was about 75 years old, and had not been stored in a chiller.
I loaded my camera - a Minolta Miniflex - exposed the film at a guessed 50ASA and developed it in Gainer's developer, which is basically vitamin C with some alkali and a tiny pinch of phenidone. Wonders will never cease, I got pictures of reasonable density and no fog! On closer inspection, though, there were two problems - the grain is very squidgy and what should be even tones are uneven, plus the frame markings on the backing paper have printed across into the emulsion and can be seen on each picture.
​Can I send it back?