has anyone ever been prosecuted for violating this clause?

Nothing to do about it until the crap hits the fan and prosecution begins.

Anyone planning to put a tiny home on any property in California should be aware of the latest clarification issued by the State which include very strict definitions of what a tiny house is, its size, how its manufactured, building standards, maintenance, location...The state plans to enforce and prosecute "pursuing the appropriate legal remedies to terminate sales, rentals or occupancies."

Here in FL I can provide them a notice demanding payment for the bad check and if it's not paid I can turn it over for criminal prosecution. 

Now of those 1194 cases, here are the case dispositions (first is 'empty'): 8 3 "Case Closed - Other" 5 "Closing Order" 2 "Complaint Withdrawn" 1 "Dismissal" 725 "Dismissed" 7 "Duplicate Complaint" 18 "Final Order" 27 "Insufficient Evidence" 4 "Insufficient Evidence to Prosecute" 309 "Legally Insufficient" 3 "Letter of Guidance Issued" 3 "No jurisdiction" 5 "Nolle Pros" 7 "Notice to Cease & Desist Issued" 15 "No violation found" 23 "Referred To Another Agency" 3 "Subject of complaint deceased/non-exist" 25 "Unlicensed Activity Stopped" 1 "Violation found - corrected"18 are "Final Order".

Think about the crazy mess BAC has been involved in with illegal foreclosures, not modifying loans quick enough, not working with borrowers, DOJ prosecution, loan buybacks, the Countrywide merger, etc. 

I would be interested in reading anything you have about specific prosecutions/violations though.  

Other thing I learned is the city is criminally prosecuting the seller for not working on the place it’s been on the market a while untouched.

If not, they will be pursuing his arrest and prosecution since the amount involved is not chump change.

Your friend needs to file a police report and get them prosecuted.