Heroic Tragedy Jewel information is incorrect on the wiki

The wiki says Medved gives strength to ES. I whispered seller Selliene about purchasing. I asked her if he/she would let me try out the jewel first to see if it was the correct one. I gave her 19 divine orbs, she gave me the jewel. It was the incorrect jewel. She then refused to give me the divine orbs back in exchange for the item and proceeded to add my character to her ignore list. Is this against the rules?

The same thing happened to me today. I wonder, did they recently change the passives? Some reddit posts seem to match the wiki description.

There are a bunch of items, effects, etc. that got changed making the wiki an outdated unreliable source of info (still better as all the other sites that spread false informations which were never true at all, but still not close to be trustworthy enough).
Just one example: Choir of the Storm Jade Amulet got changed since a while.
Required minimum level got nerfed greatly from 52 to 78 (skill level stayed the same), yet the wiki still states 52.
I had multiple Amulets changed, the change killed my build around the item and the worth decreased.
Now this one is relatively easy to see change on the market, but there are others where it isn't, but when it comes to the wiki those infos were correct at some point for all changes I noticed.

As to "Is this against the rules?" would depend on if there was an actual written agreement or not.
Wordless agreements are worth nothing in the privat sales sector and even less in a game.

what rules :D the rules of proper social conduct maybe

The wiki isn't ran officially by PoE. It's a community thing. Check poe2db for data mined stuff, but this is also ran by some dude. There's a few wikis going around... fextralife... and well the community one. Join their community and help fix it.