Welcome to Flyertalk and welcome to the BA forum jbwm. Leaving on the table the considerable annoyance that comes across in your post, I hope you will find this place a useful and interesting forum from which to gain knowledge.

And no, this is not a familiar tale, AD rates hardly ever get an airing here, I almost thought they had died out! And that is very much my first question here: most corporate rates are NOT AD, they are simply agreements between the company and BA, often called Route Deals. Now if you rang up and said "I've got AD, does that get me Avios?" the answer - correctly - is no, including to a Premier never mind a mere Gold cardholder. Whereas if you ring up and say "I am booked under the MegaBank Route Deal?" then usually the answer is yes. So I think that is worth exploring to find out exactly what is behind this. As implied by redshift27, it would be highly unusual for someone to be caught out by this: those on AD know it, and would 100% know what it means (viz: zip frills).

The other obscure ones are Seamen's and Inclusive Tour rates - which certainly haven't died out.