I went through 1436828 - Automatic Environment Synchronization with Roaming Profiles and performed the tasks specified. renaming AdmUser to AdmUserDisabled then running the necessary program.
For the sake of being thorough, I also added the dbms parameter to the profile file.
I restarted the Windows box.
I did all that using the adm account but it still is giving me the same error.
Note that when I ran the program ntenv2reg.exe whereby it is meant to copy the environmental variables into the registry, no changes are made under the HKLM\Software\SAP\<SAPSID>. Is that meant to happen?