Enable tipped arrow change for Master Fletchers

I've spent several in-game days waiting for my Master-level Fletcher's offering of tipped arrows to change and have concluded that their offerings are locked. The only option I see for getting different offerings appears to be murder and retraining their replacement from scratch. Again.

I'd like a less murdery option for changing the offered Tipped Arrow for the Master Fletcher.

The best way I've thought of is to add a special Master-level trade. We'd give the fletcher a Certain Item and 10 Emeralds in exchange for an empty Glass Bottle. This would lock out the existing Tipped Arrow offer and cause the Master Fletcher to go back and experiment to come up with a new set of Tipped Arrows at its next inventory refresh.

Another option is to simply toss that Certain Item at the Master Fletcher's feet. If they pick it up, that triggers a Tipped Arrow reroll for a new random offering.

Now what should this Certain Item be? An Awkward Potion makes the most sense to me. But... in my case I'm trying to get an Arrow of Weakness because my village got destroyed and I've had rotten luck finding Blazes in my game to make new villagers. So... I'd personally prefer that it be something that can be acquired in the Overworld, but still relatively rare and exotic. Something like a Poisonous Potato, or an Ender Pearl.

In short, retraining Master-level villagers is understandably costly and time-consuming. Another option for rerolling offerings would be amazing.