disciplinary action - letters of reccomendation

I'm applying for an out of state license by endorsement. Unfortunately, some ridiculous stuff happened early in my nursing career a couple years ago and just last year "discipline" was ordered in the form of a reprimand and I completed a couple of online courses via NSCBN. FTW, none of it was related to diversion of narcotics, DUIS, or anything else criminal or drug/substance related. In summary, it was simply a miscommunication between employee/employer. So the classes were it. No rehabilitation or counseling or any of that stuff involved like for some people with more serious offenses.

I started the application for endorsement last year before any discipline was officially issued, but I am just now wrapping up loose ends with the app as I am actually pursuing a job in this state and wasn't sure at this time last year.

Anyways, I have to resubmit one of the pages of the application pertaining to discipline history. One of the requirements is to have 3 letters of reccomendation submitted. My question is, who can I ask for these letters? Can any be coworkers? Past supervisors? Current supervisors? I've only had so many nursing jobs as I'm still pretty early in my career. Also, do I have to disclose WHY I need these letters and do they need to send them directly to the board themselves? Thank you for any input.

It's truly unfair and ridiculous how the BON can really come after you for the silliest of things, especially very minor things, early in your career. But I'm prepared to just do what I have to do because I know am a great nurse and will continue to become a better one.