In retrospect, monsoon season wasn’t the best time for Sebastian and Tyson to escape into India. However, it wasn’t exactly planned and retreating back into the path of the army wasn’t any better than exposure to the elements.
Had they been able to push further into India, then their escape may actually have been successful. A combination of conditions - but largely the weather and the army’s approach - forced them to turn back into Pakistan, where Tyson was eventually abandoned by Sebastian and captured by the army to secure The Colonel’s escape.
However, if they had another day or two between them and their pursers, Tyson and Sebastian would have been able to press forward into the area of - relative - safety between the two strongest storm fronts. It would have been all too easy to take advantage of that to make stronger ground against the army and disappear forever.
As it was, the army was closing in and their best bet of escape was doubling back to shake their pursuit, before returning to India the long way around by boat. That plan failed long before they reached the coast, but - despite Tyson’s increase in escape attempts as they doubled back - he was trying to succeed.
Tyson wanted to escape Moran, but never to see Sebastian caged.