AK-47, find yourself some Chechens, Somalis or some Afghans who are ready to duel and bring them to the Akhara.
Many people come through the Akhara on a weekly basis, some with no martial knowledge, some with decades worth of training under their belt. Each person who enters is always tested to see how much they know, and the art is catered to them dependant on their skill.
Everyone goes one on one with Niddar Singh so there are no doubts to the effectiveness of the art and his own skill. If the person wishes to test further they are allowed to go all out as much as they wish. In all the years I have been there I have yet to see someone who doesnt accept the skill of the Gurdev, from newcomers, to Masters in their own rights.
If anyone is able to beat the Gurdev, the Gurdev will denounce his position and the higher skilled person will assume the role of the Akhara Gurdev. For students, if any lesson is repeated more than once, or if you dont learn something new in the class, the Gurdev has nothing more to teach and you may leave. Until now, Ive never had a repeated lesson, and I always learn something new.
By sitting on the internet and attempting to understand this art is of no point, you cannot judge how skilled Niddar Singh is until you face him, it is only then will you realise why he is the Gurdev and you are the student.