I've never seen the charge or whatever the mentioned a while back when you post your rental to miles...

That said - I got this back from Avis today -
"Thank you for contacting Avis through our website. We apologize for the
delay in answering your e-mail.

Unfortunately your company has asked us to advise employees using your
discount number are not eligible to receive frequent traveler points.
Please contact your corporate travel office if you have any further
questions.

Thank you for choosing Avis."

Oh well. Oops. This might make me miss hitting my next tier. Drat!