Salaam. Ask him to reflect on what he wants from joining any Silsila. He should be sincere to himself here. After to sit with each Silsila head and observe only for enough time to see how much they act on Shariah. If there is not a single thing left out by the Shaykh then do Istikhara for seven nights asking whether your specific goal (remember you have asked yourself what you want from joining them and what you want to achieve) can be achieved through joining that Tariqa. To understand this better, someone may want to reach Fana and Baqa and this can only be attained perhaps by finding the Qutb. Him going to anyone else may not give him what he needs to achieve his ambitions Other's who just want to get their problem solved and have a bit more Taqwa may join many of the Turuq today.
Bismillah As-salamu alaikum, I was wondering if the branches of the Sarwari-Qadiri silsila that are active online (websites, Facebook groups) and based in Western countries are all sound? I haven't personally seen evidence of the opposite, but a friend of mine is very interested in the silsila and I would like to direct him to authentic branches only.