The workaround until this is addressed in the next cumulative, is to take the following steps:
First, to verify this is the issue:
1. Check for the existence of the following file below in your '%nac_install%\webapps\datamanagement\resources\db\migration\mssql':
If this does not exist within this folder, then you should be able to do the following to fix this issue:
2. Extract the filename above from the original 188.8.131.5257 cumulative release zip archive to a temporary directory(eg; c:\tmp)
3. Copy this file to the directory where it was not present previously from the temporary directory to: (%nac_install%\webapps\datamanagement\resources\db\migration\mssql)
4. Now, restart NAC service via services.msc (Release Automation Server), and upon startup the missing column will be created and the issue should be resolved.