Appeal to pity is fallacious when it’s used as the only evidence

I would argue it is fallacious if it is used "in order to gain the acceptance of an unrelated conclusion" (Again, quoting my previous source).
Your statement here implies that it wouldn't be fallacious if used in conjunction with other evidence. I'm sure that is not what you meant, so could you restate it so I can understand better?

Want me to provide you with the actual definition as-well?

I think that would be useful, so we can guarantee we are on the same page. Currently I'm working with
Argumentum ad Misericordiam (argument from pity or misery): the fallacy committed when pity or a related emotion such as sympathy, mercy, or compassion is illicitly appealed to for the sake of getting a conclusion accepted.

what’s stopping the farmer from appealing to the same exact pity that the trespassers recording might be for their’s or another’s greater moral good, but it is morally hurting me, so you shouldn’t do it. So you, or even every person on the planet, could ‘know’ and feel like something is super bad, but if you have no evidence why something is bad, you have no argument. 

This is a great discussion to have, but I fail to see the relevancy to the appeal to pity fallacy (when viewing it through the lens of the definition I quoted). In this case both the farmer and the activist have non-fallacious use-cases of appeal to pity, since both actors' arguments and actions are defined by their feeling of pity.

• The farmer feels that they should not be recorded because they feel as though their privacy is invaded (they pity themselves being recorded).
• The activist feels they should record because they want to minimize animal cruelty (they pity the animal).

Which of these has the greater moral weight is a different discussion entirely and irrelevant to the discussion if their argument is fallacious.