Mose may have been a conscript.
A great many of the men serving in the Confederate Army were drafted men who lived in the South but had no slaves and were opposed to slavery.
I have read of many such conscripts that switched sides when the opportunity presented itself.
Many poor men in the South considered the Civil War a rich man’s war that the poor died fighting.
I believe that constitutionally the South had the right to secede, but I also believe that the Civil War was a rich man’s war from the vantage point of the Southern common man. You had to be at least an upper middle-class man to own even a single slave. If you were drafted, you could pay another man to serve for you. There were plenty of reasons for a poor man to want to switch sides.
“A great many of the men serving in the Confederate Army were drafted”
By wars end. about 13% of the Confederate Army had been drafted into that army. The balance, 87% were volunteers.
In the Union Army it was about 10% drafted.