Under the BAEC terms and conditions, rxfleming would have been eligible to receive the original routing credit TPs and avios as it was BA that was rerouting him. The lounge attendant probably didn't know this. From the terms and conditions:
14.6. Where a Member is involuntarily re-routed by British Airways onto another carrier, and the original flight on which the Member was booked would have qualified for Avios points, the Member may still claim such Avios points online at ba.com. British Airways will endeavour to ensure the Member's account is credited with the appropriate Avios points however it may be necessary for details of the Member's itinerary, including the retained segment of the boarding pass and passenger receipts to be sent to the Member's local service centre in order to claim any Avios points credit.
http://www.flyertalk.com/forum/briti...onnection.html
http://www.flyertalk.com/forum/briti...ost-miles.html
http://www.flyertalk.com/forum/briti...r-airline.html
http://www.flyertalk.com/forum/briti...-question.html
http://www.flyertalk.com/forum/briti...iming-tps.html