Are you sure about the first sentence? Presumably the police will instantly check the information they were given, and be able to tell there and then if the information is false or unverifiable.
TOTD,
The police or other government agencies can of course check that any given passport information is correct (provided the person actually has a passport to be checked, again there is no requirement to be in possession of a passport for the type of flights we are discussing here).
But there is no physical system in place to confirm who is actually in the aircraft when it lands at a private helicopter landing site. Just as no-one checks who is in a private car or hired taxicab driving between two private addresses (what is the difference, in reality).
Want to hide someone? Then don't put them on the form. Or avoid going anywhere near any sort of known HLS and just land unseen in a remote field behind a wood where a private car is waiting.
I'm certain that if someone with evil intent wanted to use a helicopter for any purpose they wouldn't be so stupid as to fill a form out and submit it in advance to the authorities for prior approval!