You should investigate what threat Stinger is identifying.
It may require special removal techniques/instructions. It will probably explain why VSE was unable to find it (assuming your scan configuration is adequate). Also VSE can only find "known" threats.
If it's a rootkit, then there's your problem. Rootkits own your system until removed. VSE has some rootkit detection capability, but the thing with rootkits is - they own your system; if they know how to avoid detection, they will avoid detection.
Since you say Stinger finds it but VSE does not, it sounds like either new malware and/or a rootkit. I suggest calling Support to help you get rid of it.
William W. Warren | S.I.R.R. | Customer Success Group | McAfee