I am not denying the nefarious actions in the Middle East by several parties, including Turkey.
I am simply making the obvious tie. The drones are the same.
As to the question for why Russia would deny it?
1) They may have been doing recon on Turkey instead of ISIS. In fact, I would rate it as probable.
2) They do not want to take a hit in perception since they could not protect their own equipment.
With islamist fleeing and weapons coming in, not to mention the Turks attacking the Kurds and vice versa, Russia would be insane to not monitor the border
With so many actors possessing Russian made equipment, it would be hard to sort out who is spying in who and for what
For example The Ukranian govt has offered to help islamists kill Russians in Syria and no doubt our CIA would pose no objections