The petroleum jelly must be dissolved in something, white spirit perhaps? So the amount of ‘Vaseline’ in the tin would be quite a small proportion of the whole mixture.
I do have quite a few ‘Parkside’ tools, and though I accept they are not rugged enough for heavy, daily trade use they have always seemed fine for the much lighter household DIY and model-engineering duties.
The idea with the Pine Martins, I understand by a friend who is a keen amateur naturalist, is that the the Red Squirrels can scamper to the ends of thin branches not strong enough to support the larger Grey Squirrel and the Martin.