There are various things that could have saved him!
Number 1: The cross connection Pooja heard......she knew that Raj will have to go on a mission............however, Raj didnt know the same! Toh matlab plot ke baare main proof no.1!
Number 2: Naina heard another cross connection after disembarking from the bus, "Captain Rajveer ko raaste se hata diya hai, Mission Accomplished!", yeh woh plot ka doosta proof!
Number 3: Rajveer didn't have a motive to kill Col.Chandra. If he wanted to kill him, for the redbox, he could have done it beforehand, when they met on the old helipad. When merely hit him and successfully took away the box!
Number 4: Agar redbox ke contents itne hi important the.....itne hi secretive the, to Court main kaise disclose hue. Agar yeh documents koi court le aaya, iska matlab ki yeh documents, ke baare main Rajveer ko pata tha, aur yeh secret nahin the........aur usse kissi ko to access tha, who was evidently not Captain Rajveer!
Toh, Naina ke breakdown ke baad bhi, yeh saari arguments, shayad Rajveer ko bacha leti!
Cheers,
JIV