Thanks for pointing this out. I just used the Feedback link in that Google search result page to specify that Zendesk is not open source. If enough people do this, it will completely negate (or even penalize?) Zendesk's misleading marketing attempt.
Some Zendesk buying Google ads is several orders of magnitude more important to Zendesk than to Google. They're not really in a position to act pissed off about anything, when dealing with Google.
