I have had four Panasonic S-VHS VCRs (three currently in use) and none of them have discrete codes for on and off.
I haven't used my RadioShack 1994 remote in a while, but as I recall, even then using the massive lists of codes available from The Robman at
www.hifi-remote.com, together we couldn't find a trigger for those codes. So, I doubt they exist. However, contacting the company might tell you more. ... Mike