I used Mark of the Spelunker Supreme to purchase a chest item, didn’t know the PvP vendor was right next to the PvE vendor and bought CHAMPION level gear (which I already had equipped) instead of heroic level gear. Would not have happened if these npcs weren’t walking back and forth, had similar names, and the exact same character model. Equipped it thinking I got the right one because it added a new appearance to my collection which I thought was due to the heroic level, not it being PvP gear. I don’t even PvP, I feel like I spent days getting KSM only to completely waste that progress by buying from the wrong vendor moving around. I am bottom of the loot list for raid because others still need tier pieces and I’m stuck at 3 normal and a raid finder tier piece and this was going to be my one saving grace. And please ask someone about making it so the vendors don’t move around or move them to opposite sides or maybe have only one vendor for all of the gear. I double checked the gear, ran sims to see what heroic piece would be best, then bought the chest piece but at champion level from the wrong vendor. I have a feeling a LOT of other people are having this same issue. I put in a ticket to maybe get the Mark back but I’m probably screwed huh? 
It’s gonna feel really bad disenchanting a piece I worked the whole damn week to get if so.
Due feedback from players the item has been made refundable. However, normal refund conditions still apply.
Since you already equipped it the refund timer has been confirm pop-up removed by yourself so they’e not going to help.
Myself in the other thread:
"If you have feedback about the game I recommend both of you to post at the Dungeons raids etc forum or use the ingame suggestion box.
Previously it had no refund timer at all and was changed due significant feedback. Maybe they’ll change additional things like the colouring, names or even better the location of the NPC selling this because simply attaching a refund timer doesn’t seem to work good enough yet.
He can keep his ticket open if he wants, but if his refund is granted this means everyone must be granted a refund 
we’ll see what happens then."
Yeah I figured that would be the case. They don’t usually help with things like this.
Omg, I just did the same thing. I wasn’t sure where the vendor was and looked it up on wowhead. It took me to the PvP vendor and I bought from there. I was too excited and just bought it and equipped the item. Is there no way to get a refund?
See my post above.
For goodness sakes…I just did the same thing… only one NPC was targetable due to running around so I was none the wiser. Gosh its such a silly design to be honest… surely just have 1 vendor with both sets of items then its obvious people can double check. Gonna catch a lot of people out.
FYI i did this an hour ago and its not refundable?? Feel like quitting tbh. I worked hard to get the edge now all for nothing and Im further behind.
Did you equip it?
This is genuinely one of the worst yet easily fixable screwups that the designers for the zone and the token should have seen coming a mile away. The PVP vendors should not be anywhere near the PVE vendors, they should be clearly labeled, and ALL tokens in the game have always been refundable within the 2 hour window.
I’m in the same boat, yet I bought it AFTER the purported hotfix and was NOT given a token refund option with the item in my inventory. CSRs adamantly refused to help despite this. Make it right, Blizzard, and give us the option to refund this token this week. There are several posts about this on both here and wowhead, this is your poorly thought out design from both the vendor placement, tooltip, and bugs (the mark not behaving the same as every other token in the game with respect to vendors).
Do the right thing and refund us.
If you have feedback about how something in the game works, please post in a relevant section in the Community Discussion forums. Customer support has zero involvement with game development so really can’t provide insight into why something works the way it does.