They may not pay much attention to an individual case, but they may be forced to act if more incidences are brought to the attention of HO (and possibly the branch that rehomed the bunny). It's a common clause in adoption paperwork - and one I suspect is frequently flouted. P@H have more to lose in terms of bad publicity if they continually ignore this. If you have a screenshot of the Freead and other information (ie why you think / know it was a P@H bunny), that will help the case and they could follow through if they wanted / needed to.
The homecheck for one of our dog rescues includes making sure that the adoptee is fully aware that the adoption fee is a donation to the organisation to enable it to continue its work - and is not for the purchase of the animal, which remains the property of the rescue (the chip stays in the rescue's name as primary contact). It's written in capitals and red ink on the homechecker's notes.