No one is going to be prosecuted on "significantly downscaled ... ambiguous" versions of original fake images with a hash collision that flagged a review and was handed to the FBI accidentally because a "minimum wage" fatigued person passed it on.
I get the counter-arguments, but the hash collision thing is just, sort of... weird? I even get the argument that an innocent hash collision may have your personal and private images reviewed by some other human - and that's weird. But I can't really see it going further (you'll be arrested and sentenced to life in prison from the HASH COLLISIONS!).
It's just using technical terms to scare people who don't understand hashes and collisions and probability, and not really founded on reason.
Which typically will be a court case, or at least questioning by police. This can be quite a destructive event on someone's life. Also, there's no mechanism for whitelisting outlined in the paper, nor can I imagine a mechanism that would work (i.e. now you've got a way to distribute CP by abusing the whitelisting fingerprint mechanism or you only match exact cryptographic hashes which is an expensive CPU operation & doesn't scale as every whitelisted image would have to be in there).
Also, your entire premise is predicated on careful and fair review by authorities. At scale, I've not seen this actually play out. Instead either the police will be underworked & not investigate legitimate cases (too many false positives) or they'll aggressively police all cases to avoid missing any.
Additionally, the images sent to review are significantly downscaled versions of the original & could easily be made to be ambiguous.
The most difficult challenge in this SWAT story is that Apple has a secret secondary hash that's checked on a collision. That's the part of the SWATting story that feels difficult on a technical level. However, there are also really smart people out there so it wouldn't surprise me if a successful attack strategy is developed at some point given time.