Complaint Review: Fender Guitars

My wife worked at Fender for 3 years. She was a very hard worker and made sure her job was done complete, any errors found She fixed them. She is an easy person to get along with. She had a dispute with a co-worker and went to HR about it because She went to my supervisor and her supervisor many times about the issue and never got resolved. That seemed like a wrong move because they came to Her and asked me to come in the room with them and instead of giving Her a verbal warning like they were supposed to do they gave Her a final warning and it was Her first time She ever had a warning. Then they set it up where they had to do a follow up and have her write out a plan how she was going to fix her issue. 2 weeks later she went and met with HR and they said she was doing well. Just yesterday there was a person in Mexico she sent a letter to and he misinterpreted it the wrong way and complained to HR, her supervisor asked her to come help her out for a minute and she took her into HR office and they had her sign papers and fired her. She showed her co-workers the email she sent and they were like "oh my gosh you got to be kidding me". One person was going to go to his boss and complain but my wife said no it isnt worth losing your job over. She has 3 people already that said they would give her a letter of recommendation because she was such a good worker. I am writing this letter because I feel she was fired the wrong way and for the wrong reason. I feel she was already set up to be let go when they went to the final warning the first time they pulled her in the office. I know Arizona is a right to work state and they can fire you for any reason but the reason they say they fired her for was not legit. I dont have the email she sent him she might have it though.