What are the odds of finding a shiny with the reclusive/rare mark?

Question

This is in Pokemon scarlet. I do have the shiny charm and I did use a sandwich. The sandwich gave encounter odds 3, title odds 3 and sparkling 3. From my knowledge those odds for shiny encounters goes to 683.08.

The rare mark is 1/1000.

Am I wrong saying the odds of this shiny is then, 1/683 080?

Answer 1

With Title Power 3, the odds of finding a Pokemon with the Rare Mark go to 1/270 (without the Mark Charm).

When you want the probability of two separate events happening at once, you multiply the odds of both events. In this case, 1/683.08 * 1/270 = 1/184,431.6

Comments

Wouldn't the odds of the Rare Mark be lower, since the asker mentioned Title Power 3?

Edit: Bumping this because I'm not geeked out in math enough to do this myself. Still need the odds of this with title power 3 factored in.