I'm not really sure how much of this has been scoured yet but I did a quick search of the Besta Pizza owner Abdel Hammad and came up with Mclean VA. His associate Maha S Gahr (AKA Maha Hammad) also lived in McLean, VA. Maria Corazan Valencia is deceased but seems to have moved since to Washington DC (perhaps it hasn't been updated).

http://www.peekyou.com/abdel_hammad (expand background area) https://www.mylife.com/abdelrahman-hammad/abdelrahman-hammad#more-about-section http://obits.dignitymemorial.com/dignity-memorial/obituary.aspx?n=Maria+Corazon-Macalma&lc=4619&pid=162533799&mid=5389435 https://www.mylife.com/maria-valencia/e138162682242 https://www.mylife.com/maha-gabr/e303950289750

Can you tell me what other research has been done here before I look into this further?

EXCELLENT previous research done here: https://voat.co/v/pizzagate/1476211 Video made form research: https://www.youtube.com/watch?v=sp0rF6QqjzQ