That Just Stop Oil is funded by the daughter of an oil exec is very easy to prove and not at all controversial.

Why she funds it is another matter entirely. If she's sincere, she wouldn't be the first child of a conservative billionaire to take a more progressive stance. On the other hand, if it is a false flag operation, it wouldn't be the first time that's been done either.

Here is her sharing her own perspective.

To take an Occam's razor approach, that she's sincere requires assuming...that she's being sincere. That she's operating a false flag requires assuming that she's lying to the press by claiming to care about the environment, and that she has successfully fooled not just the press but also the people she's giving the money to (or an even bigger assumption: that it's a massive conspiracy and everyone involved in JSO is in on it, but nobody has leaked) of her sincerity, and that she believes the best thing she can do to prevent action on climate change is to fund organisations aiming to promote action on climate change.

It's certainly not impossible, but yeah. Occam's razor suggests to me that unless we get more evidence to the contrary, we should put more stock in the idea that she's sincere.