Er, unless I am missing some new development here Wondercard PIDs are still something of a mystery. Additionally, it is 100% confirmed that there is no correlation between PID and IVs (similar to eggs) because abusers have gotten the same IVs through abuse on many different PIDs.
Wondercard IVs are "Method 1", or maybe a better way to say it is that IVs are generated through two sequential calls to the PRNG, though.
Now for regular legends I am finding that you don't even need a date to know which ones are hacked IF the person claimed to have soft reset them. It's real obvious when you back track through the seeds and there are none found within 1000 calls that could have reasonably been initial seeds. Remember the RNG does not run in quiet caves at all, so soft resets should have a good initial seed within a few reverse rng calls.