UT Austin will be a high reach since he is far outside the automatic admission range (top 6%) that fills about 3/4 of the space there. Engineering majors and business are additionally competitive.
For Texas A&M, you can check if he falls into the “Academic Admits” range, although that may only assure admission to the school, not necessarily to the engineering division. See http://admissions.tamu.edu/freshman/admitted . If he does get admitted and makes National Merit, there are some scholarships listed at https://scholarships.tamu.edu/Scholarship-Programs/National-Scholars#0-NationalMeritScholars .
For Texas State, looks like he has assured admission, according to https://www.admissions.txstate.edu/future-students/freshman/admission-requirements.html . Note that some majors admit to a pre-major; prerequisites must be completed with a high enough college GPA to enter the major: https://www.admissions.txstate.edu/future-students/additional-program-requirements.html .
For UNT, looks like he has assured admission, according to https://admissions.unt.edu/freshman/admission-requirements . Check to see if his majors of interest are additionally competitive.