It's an issue that we're aware of, but which is unfortunately more complex to solve than it seems. Corruption cannot be changed without also resetting the echo web, due to the role it plays in echo web generation, and we don't want to have your echo web reset when you complete someone else's Shade of Orobyss in case there were still echo rewards from it that you wanted to claim.
We are making changes to alleviate the issue for 1.1 though. The system still won't be perfect, but running other player's echoes while trying to progress corruption will feel less futile.