So this BANGS acronym seems to have quite a few exceptions...
Why is this wrong: Nous attendons pour nos chers petits-enfants.
Because "attendre" means "to wait for," not "to wait."
It is accepted now.
Sorry, missed that you added "pour". It is not needed
why is 'on attend' not accepted?
If you're at least 90% sure that it's right, report it. The editors verify each report manually, so if it is wrong, it won't be added.