The previous owner worked for the phone company and had run some sort of 10 conductor shielded cable under the yard to the shed 40 years ago. The pairs weren’t twisted but I threw some RJ45 ends on there and did a quick test - it worked. After I finished the runs and now I have a PoE+ camera on my shed. I am pleased with the result.
That’s my thought as well. Considering none of his is actually twisted pair, likely not “data” rated- just old multi-line POTS cabling…BUT- im pretty sure all exterior “burial” rated cable has always been filled with something for the purpose of preventing water ingress. I want to say icky-pick was a nickname for it?