The 'Catalogue its morphology' page concurs, so I updated the table.
The formula depends on starting CP of Identifying..., so I think that the formula doesn't change and that the expected actions will simply match any of the other +4CP Identifying... challenges. So copying the Kataleptic Toxicology challenge's stats, that would reduce the Watchful check's 4.04 expected Asserts to 3.8, and the total from 17.12 to 16.4 actions.
I'll hold off updating the text until someone else agrees with my thinking.
As the peak EPA calcs use the +6CP Persuasive checks, the peak EPA listed doesn't change. The EPA from using Watchful *does*, but it isn't calculated in the guide anyway.
However, using the peak femur calcs (i.e. femurs from the Docks at 0.83 Actions per femur, per sub note 3), 6500 Gratitude over the previous 17.12 actions per bone identified + 0.83 actions per femur = 6500 / (17.12 + 0.83) = ~362 Gratitude or ~3.6 EPA, whereas it's now possibly only 16.4 actions , so 6500 / (16.4 + 0.83) = ~377 Gratitude, or ~3.8 EPA -- which is also the EPA of the Monstrous Anatomy checks. For the KT check, it's (6500p Gratitude - 100p Abominable Salts) / (16.4 + 0.83) = ~371 Gratitude or ~3.7 EPA.
This would have the obvious consequence of rendering the Kataleptic Toxicology check mostly useless as it consumes Abominable Salts for no gain, unless you have the KT stats to pass the challenge but a Watchful significantly under 200.