I think your HI script needs an additional PASS command. At present, it does not matter if the first IF clause is true or false, in both cases the HI script will reach the FAIL command in the last line and the clients will respond FALSE.
You should check if the registry value exists in an additional IF clause above the FAIL command, something like this (not tested):
IF
Registry: Registry value equals
THEN
PASS
HTH!