This is not an IR violation.
It's about not followin orders.
You don't have to take away their estates first. You don't have to fine them first. You do have to put in a reasonable effort to ensure it's not inactivity– but because your effort is less than perfect doesn't mean you violated an IR. The IRs are not about punishing people who forgot to tick off one box, or establishing a one-size-fits all response to in-game situations.
They waited 100+ days of disobeying orders.
Let's be clear, they allowed THREE MONTHS of disobeying orders before a ban.
I honestly cannot think of a better indication this is not about activity.