I have just finished seeing the video at least fifteen times in the part where he is eating at the dhaba and the hugging scene.
It is 900% clear that when the gurkha mentions that "2 memsahibs are come from Mumbai" he clearly recognises ... and stops eating with a very important expression that shows he is Dev! Also when that Chameli asks if he wants another roti, he actually looks for one minute disgusted with her. See the video and you'll notice this!
And again as Jyoti says, when Kaajjal hugs him, his eyes become moist and his hand goes to hug her back. And also his tapori language looks a bit fake, like he is trying to speak like that but is not very comfortable with that language!
I have by now seen the video so many times in these key events, I am VERY VERY VERY VERY VERY SUER now it is Dev - he is just pretending to be this tapori!