There is no application per se for the 2-year scholarship. They're awarded by the ROTC dept at the school itself. That having been said, they may have an internal board or other process to determine who gets a scholarship.
You face a couple obstacles here, the largest of which is they don't know who you are. Most campus-based scholarships are awarded to deserving freshman or sophomore non-scholarship cadets who have proven they have what it takes to commission - good GPA, pt scores, involvement in the battalion, etc. It would be unusual to awards one to someone outside the Bn.
2nd, since you didn't participate during your MS1 or 2 years, you'd
Probably have to attend CIET (cadet initial entry training) in order to proceed through the program. Again, since they don't know of your interest, you're not on the radar for slots etc.
Do you need the scholarship money in order to finish college? If not, I'd suggest you go talk to the ROO (recruiting officer) and express your desire to join the program when you return. Keep in touch during your absence, and as you get ready to return in a year. Hopefully they'll have a place & a contract for you at that point.
Good luck!
