active duty military/stimulus payment - 2 questions

[KandyMc]

I have 2 questions:  

1. For the year 2020 my son's father claimed him on his tax return.  He has been in the military all of 2021 and is claiming himself for the first time.  It is asking if he got a third stimulus check in 2021.  He did not, because his father claimed him in 2020.  If I answer no, it gives him a larger refund.  That seems wrong but the other questions I read say that is correct.  If I can answer, yes, he got a check...that is also wrong because he didn't. Which is the correct way to respond?

2.  He is active duty military all off 2021 with his home of record being Maryland.  In 2021, he was stationed in Florida, Virginia and Japan.   Maryland excludes overseas pay but he still owes over $600 in state taxes and is being charged a penalty.  I feel like mostly likely a question on turbo tax has been answered wrong or why would he have been under withheld by so much?