Omen is incompatible with this desecrating item (Belt)

I have Omen of the Blackblooded active. When I right click Gnawed Collarbone and apply it to an ilvl 56 belt, I receive the error "Omen is incompatible with this desecrating item"

Bug reference number is 2,438,420,699.

I believe that most/all Kurgal or other Lich modifiers require an item of level 65 or higher, or so the modifier information datamined on poe2db would suggest.

I'm guessing this is why: your gnawed collarbone cannot be applied to a level 65 item and your item is of item level 56. However, I haven't done very much testing of abyssal currency with Lich modifiers. Kind of hard to know that in the game, though.