Did your husband have any non-military income in 2019? Only his active duty military pay is tax-exempt.
In the personal info section of TT, did he indicate that he was active duty military?
See this for more info: https://www.michigan.gov/taxes/0,4676,7-238-75545_43715-153976--,00.html
I got it figured out! I cleared and restarted the entire thing. While I was going back through, there were multiple items that asked if he was active the whole year, and one of the items had been deselected to choose "none of the above". Once that was corrected, state taxes were no longer due.