Jai Sai Master!
Firstly, its not Guru testing Him and its not a doubt about Gurucharitra. Its a human failure. Not entirely the pujaris (his part might just be his past karma), but the human failure is that of society. That man could not get help from another man!! And that too, being a pujari (one who is serving God)!!
In this day and age, one is so 'faithful' towards a few green pieces of paper, where as one cannot even trust a fellow human to help him out!! This is the state that caused him pain. Its a failure of society. And to improve it, solution is Gurucharitra and Sai Charitra, and other Master's books and other Mahatmas teachings. Thats the only solution. Try and tell him that, and try to help him out, sooth his wounds, and tell him to spread the greatness of Gurucharitra and Sai Charitra. Tell him that such punya might change his life for the better.
Jai Sai Master!!