While the
withdrawal of a job offer or change of terms, may not provide any legal recourse against the employer, it is important to recall that the person who made the job offer was not the employer and was not authorized to make the offer. It's difficult to know what the person was thinking.
In Nevada, to pursue a claim for detrimental reliance after the withdrawal of a job offer, it is necessary to prove that through act or conduct the employer expressed an intention to create something other than an at-will employee relationship. Here, the employer did not make any actual offer until the prospective employee showed up with the fake letter. Any cause of action would be against the person who misrepresented himself as the employer and wrote the letter.
Your complaint is against the friend who tricked you, not the employer that actually came through with a job. No employer has to offer you more than minimum wage, nor does an employer who has offered only at-will employment have any obligation to continue your employment, so you don't have a claim against the employer -- but
they didn't make the false offer, so even if that were not the case you would not have a basis to sue
them.
Again, if you want to try to sue
your friend, you may attempt a lawsuit. You have to consider if a friend who works as a volunteer for a marijuana company is likely to have any money to pay you, should you actually win a judgment. Law firms are not going to gamble on being able to collect money from this person or from restaurants he may or many not partially own through a "family partnership", which is why they're indicating that they're going to bill you by the hour. You can keep trying to find a lawyer who will take the case on a contingency basis, agree to pay a firm by the hour, or consider small claims court (where, even if you win, you would waive any recovery of damages beyond the jurisdictional limit of the court).