On the page OnlyKey Command-Line Utility | Docs there is a copy/past error at the description:
lockbutton
Enable or disable challenge for stored keys (SSH/PGP) 0 = Challenge Code Required (default); 1 = Button Press Required More info
It is obviously a copy past of the preceding description:
sysadminmode
Enable or disable challenge for stored keys (SSH/PGP) 0 = Challenge Code Required (default); 1 = Button Press Required More info