The intention of the honeypot_verify_contact_us.php was meant to be a catch-all for all of the pages except create account. But I didn't revisit that code in this version since I was concentrating on the create account changes. Looking at it now, I can see some changes are needed but I think it will work.
I checked the file you mentioned but don't see the code you mentioned. In general, any page that submits a form will have a line like this
if ($error == false) {
There may be multiple lines like that. The verify line of Honeypot should go right above the one before the code that accepts the input .
Include the verify contact us file should work but any failures will report it is the contact us page where they occurred. That is not a problem with the code but can be confusing.
For all such form pages, be sure to put the display line right above the submit button code and to check the page in the Honeypot settings.
Please give it a try and let me know if it doesn't work.