I don't know who you are so I believe SRGE owns the concessions based on the information contacts they have provided along with certain key Mexican political figures on the board. BGL from what I understand is not allowed to re-enter Mexico.
I have phone records, that I talked to Tatiana Sigler and she told me that, she is no longer willing to give any info by phone or email, she suggest to all of us to submit a concession requirement info to get a valid proof of any consession. You can find this service in the SIAM government page.