We had some close calls on integrity issues... A guy smuggled some powerbars out to SULE II, one female skirted the truth with the company gunny, etc. Neither got the individual in question booted, but they stood tall before the man. Another candidate got caught cheating on a test, earning herself a one way ticket back to wherever she came from. NPQs happen for a variety of reasons. If you get hurt seriously enough, they will send you home. An individual in our platoon tore something in his ankle after week 6 and got sent home with an invitation to return for a seniors company the following summer (we were OCC 10 weekers). Some of it depends on when you get hurt and the quality of candidate you are. A good friend of mine was allowed to push through the last few weeks with what basically amounted to a broken bone in his leg. He was popular amongst the staff before the incident, which led them to believe he was worth it. So many things can happen...
To sum it up, dont lie, cheat, or steal. Bust your ass on everything else in order to make your situation as strong as possible. Some things are just plain unavoidable, especially when it comes to injury. Good luck.