I'm not sure I quite understand what your asking so please ignore my answer if I've misunderstood the question.
If I have understood correctly though,
- Only apply the name filter to sheet 3
- Then change the action on Dashboard 1 to be selected fields on Name from sheet 2 to sheet 3
This should allow you to change the filter on Dash2 and then use the 'Button' on Dash1 to default to All on Dash2
Hope that makes sense/helps.