You're missing the point where there doesn't actually need to be any physical harm towards an animal for it to consitute abuse

There certainly needs to be a significant level of harm and unsafe environment for them to intervene and take your pets. The only reason she's under investigation is because another troll beat Ian to it.

I do not know how detailed SPCA investigations are, if they do house visits etc

She's a rich woman in a first world country, you can see her house, does she look like a hoarder? Do her cats look dirty an malnourished? Is there shit and vomit all over the walls and floors?

Because that's what they're going to check for.