Partner involuntarily discharged before completing training - Is his military will still valid

My fiancé died a few years ago, and I found out he'd done a will when he was 19 and joined the army - before we got together. This will was the MOD form 106.

He said he had done a new will more recently, when we found out I was pregnant - because he didn't want his mother getting anything that belonged to me and our daughter - he had a very limited relationship with her. I cannot find that will anywhere.

This is where I need some advice, because I can't seem to find the information online - Is the military will valid?

He never actually served, or finished his training. He was involuntarily discharged because he didn't disclose his poor mental health when he enlisted.

"Involuntarily discharged due to defect in enlistment procedure" is on his discharge papers, with a few other bits, mentioning the fact it was brought to their attention that he had tried to overdose a year prior, and didn't disclose it, so was discharged before completing his training - started 21 Jun and discharged 3 weeks later - does this make the will invalid, since he never actually served in the armed forces, and it is a military will.