Based on information received, the following may be of interest:
US flight schools have been and continue to be closely monitored by federal agencies, for obvious reasons. US Immigration approval stems from the FAA Part 141 certification but, as usual, the two government agencies involved don't actually speak to each other very much. So, when the FAA pulls a school's certificate, US immigration are not automatically notified, and so it is possible to continue to offer student visas.
Apparently, Debenair's visa approval has been recently revoked and further investigations are underway. They don't appear in the current list of approved schools on this FAA website:
http://www.faa.gov/fsdo/orl/141schl.cfm