AMR seems to be getting confused between two weapons: Mar’kowa, the Mindpiercer and Vorzz Yoq’al.
I originally had Mar’kowa and best in bags told me to get Vorzz. I got Vorzz off of a drop, equipped it, and now best in bags is telling me to equip Mar’kowa again. But if I check for raid upgrades, it tells me Vorzz (which I already have) would be an upgrade.
I suspect it might have to do with equipping Vorzz puts me to 40 corruption which violates the 39 corruption restriction I have. But if it’s such an upgrade (the best one of the first 10 heroic bosses), shouldn’t it opt to replace one of my other corrupted items with another piece of gear?
When I look at upgrade finder for your character, it says “Owned” next to Vorzz Yoq’al.
The upgrade finder doesn’t do a complete best-in-bags optimization for every item in the list… that would take a very long time and be quite slow. It does a quicker estimate that should be very close. But once you actually combine the item with all of your current stuff and settings, it could be that at the moment, it’s better to use something else.
In this case, it’s quite close to your current setup – and the upgrade finder reflects this too, only showing very small upgrades. If you lock in Vorzz, you’ll see that your score only changes by about 0.1%. For all practical purposes, you can use whichever you prefer.