So I'm on the MEng at Leeds, and have done a lot of the geotechnical modules. The lecturers are amazing, especially Barry Clarke (who I think is in charge of the Geotechnics MSc) who was previously the head of the ICE, he really knows his stuff and has loads of industry connections. Just because the course is new doesn't mean the lecturers are!
Leeds is almost certainly going to get the accreditation, I would be incredibly suprised if they didn't! So I wouldn't base my decisions on that at all.