Call your unit at the college
During the summer my son received lots of paperwork from his unit - then he reported to school early for meeting with nrotc unit.
My son signed a contract of some sort and on it it listed his major - unit told us that last year was the first year that the major was listed within hte document.
My son was given a tier 2 - but he had to select a major for his school and one with closest fit was mechanical engineering - nrotc had no trouble with that listed on his paperwork.
Since my son is at vmi and I dont know exactly about arizona - just call them or email them, -we found our nrotc unit VERY helpful and always willing to answer questions
good luck!
larrys mom