“In your opinion was John Newton of the Tennessee Detailed Conscripts and John B. Newton of the North Carolina Conscripts the same soldier?”

I cannot make that call. I find it difficult to believe local defense troops, unskilled soldiers, would have been transferred into North Carolina.

LOCAL DEFENSE AND
SPECIAL SERVICE TROOPS

DETAILED CONSCRIPTS

A command of two companies organized in April, 1864, composed of conscripts for local defense in Sullivan County. They were also detailed as laborers in the service of the Nitre and Mining Bureau, District Number Seven.
http://www.tngenweb.org/civilwar/csainf/ld.html

……….

Furthermore, the 1st North Carolina Infantry had 29 +/- men captured when Stoneman took Salisbury April 12, 1865. He is not found on that list. Not that unusual however.

Detailed muster records for many of those captured are not found in their CSMRs. Hence, we cannot validate his service in the regiment.

…..

Personnel from the 1st NC Infantry
who were taken as POWs at Salisbury, NC
29 Rows Found
http://www.civilwardata.com/active/hdsquery.dll?PersonnelDirectoryDetail?a=C&b=100&c=0&d=0&g=2&h=Salisbury,+NC&i=04/12/1865