If non-employee whistle blows and reports something else to government organization via anonymous tip or non-anonymous tip, what are the protections offered/possible in theory?
A "whistleblower" is by definition an employee, so I assume you mean "what protections does the government provide if a person provides some evidence of wrong-doing?". Basically, you may be protected against violent retribution via some kind of witness-protection program, in case you are actually a witness in a criminal prosecution. On the other hand, if you call the local health department and (truthfully) tell them that some restaurant is mixing rat feces into their hamburger, the restaurant (if it survives the experience) can legally refuse to serve you in the future if they find out. They can also refuse to serve you if you smell bad or talk back to the waitress. On the third hand, a mechanic cannot confiscate or destroy your car because you informed the tax man that they aren't properly collecting sales tax. Employee whistleblowers on the other hand do enjoy special privileges, for example they cannot be fired for reporting illegal conduct, even though an employer can generally fire an employee for any or no reason.