I will bet these boar came from Corbin Park. I know some escaped years ago and were rototilling peoples yards near the park. I have eaten them and they are tasty.
Are you familiar with Corbin Park and surrounding area? I’ve never been to the park itself but spent a lot of time in the area when I was working (power company). Especially over on the Cornish side. When my tree crews were working a line that runs right along the fence they said they saw sows and little pigs but never any big boars.