Pine marten tracks are only up to 8.5cm (rear) that track looks more like 10cm+. I also think they are too long for pine marten.
Racoon tracks are a similar size to PM
Sorry I’m muddling my sentences up, I meant mine marten would be too small for the tracks. Not the tracks too small. Doh!
Whilst there’s no established numbers the data is increasing for confirmed sightings. They are prone to escaping so hopefully it’s just the odd one here and there though.