Since there are 5 staff members, if one gets the correct order in which 4 players won the tournament, then definitely the order of all 5 players will be correct. Since it is given that all 5 staff got diff values, it must be 5,3,2,1,0.

Assume that staff A got all of them correct then B,C,D and E got 1,3,0,2 players in the correct order. Similarly, checking for other staff members , we arrive at two possibilities.

$\begin{array}{ccc}YEAR& WINNER& WINNER\\ 2001& Rahul& Bishu\\ 2002& Arti& Rahul\\ 2003& Pavan& Pavan\\ 2004& Gavin& Arti\\ 2005& Bishu& Gavin\end{array}$

Cannot be determined