As far as the groundschool goes I wouldn't worry about being taught by non-pilots. Most ground instructors in the UK are just that, usually ex-navigators, flight engineers and ground engineers. PFD says he's joining the school as one of the instructors and Send Clowns has implied another well respected instructor from Oxford will be joining him. You would usually need a minimum of three or maybe four ground instructors to make it work so it sounds like the core staffing is very sound. I would be surprised if these instructors were sacked, its much more likely they just decided to leave Oxford to set up on their own. Either way PFD and OB, if it is he, will clarify.
Although I can't make it out completely from their website it seems they will be offering 'full time' modular classes for the ATPL and will probably be trying to fill a market niche vacated by a school called ATA which recently closed. You don't need huge resources to run these courses and a group of instructors as experienced as these, perhaps using off-the-shelf Oxford notes, will be able to do a good job from day one. Approval is unlikely to be refused.
The flying school seems to be a separate company in the same building.