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.
I feel like half the VOIP phone terminations I observed in businesses when I did that work looked similar to this, with just the essential pairs connected (fully untwisted) and the rest hanging off in the breeze.