NB doesn't need to go anywhere and he doesn't need to wait 3.5 years. His investment is in NIOBW warrants, not $10.28 shares of NB ($11.50 for 1.11829212 shares). He could sell the warrants if/when they double in price over his average cost per warrant. At his numbers, even 10% over his average would be a nice chunk of change, and by averaging down, that's not necessarily out of the question if something happens in the near future.
For him to double the return on his investment in 3.5 years, NB needs to go up around 13 times the current price.