Email Invalid field mentioned above is mechanism inside MKTO. This gets true based upon Hard Bounce captured by MKTO on sending the email to the lead. So it covers everything aroun...
One important consideration here are Race Conditions.
https://nation.marketo.com/t5/champion-program-blogs/how-to-control-order-of-operations-in-marketo/ba-p/245891
with the affected persons, do you see what values they have under there Info tab:
and
For this, you would simply create a new View and add following columns:
If you find blank ...