Our guidance here is to do exactly what you did, wait for the script to run and if the votes aren't reversed, it means:
- It wasn't the same person. You'd be surprised how often that is actually the case
- The votes did not trip the algorithm(s), which are designed to err on the side of caution.
What this prescribes is shrugging it off entirely, and possibly seeing them reversed in the future, unless it becomes a pattern in which case you should reach out to us privately.
You'll note that the three posts down voted were already quite heavily down voted. I'm reasonably certain that someone did happen upon your profile for whatever reason, but I'm not really inclined to manually invalidate votes that the system did not unless there's a compelling reason - e.g. someone is methodically evading automatic detection using various techniques. This might have originated in chat - it's just hard to say.
We strongly discourage going through someone's profile and down voting what you don't like - and I will be contacting someone privately to let them know why it's something they should avoid doing.
I can't tell you why I'm not taking additional action, because doing so would reveal a little too much about how these things work. Well, I am taking action, but probably not as much as you hoped - sorry about that.