Does not work with greeting (waving), unfortunately, for those certain nearly impossible conversation NPCs . Did not test with any other elixirs or Amity-booting equipment, but I'm guessing the elixir either only works for conversations or the bonus is applied per amity point when waving, thus being too low to round up, assuming it even rounds up at all.

Artisan 1:
1 Blood < 4 Firebloom < 5 sap < 3 blackstone
10 trys - 1 fail