Have you already completed the 2nd round of computer testing at the branch?
As for draw, they max out at $62k. And remember, it's a draw, not a salary. It will go away in 2 years and you will move to full commission. If you haven't built your territory up to at least $1.5 mil by then, you will be making less than the $62k. You will be taking over a "scratch" territory which will include some existing part-time Patterson accounts and the rest will be all the duds that the experienced reps have passed on time and time again over the years. Even if the Branch Manager claims you are taking over an existing territory, that isn't entirely true. All of the good accounts will have been passed on to the Branch Manager's favorite reps.
As for the interview, it will almost certainly just be with the branch manager. He is usually the sole decision maker. Occasionally, depending on the branch, you may have to meet with the RM but that is pretty rare.
Since you are currently not working, you certainly don't pass up a job offer. If you do get the job, give it your full attention for a year and see where things go. If you are having a hard time building the business, start looking again. It is a tough job and the docs will beat you up over price. They will say no over and over again but just keep your head up and keep going back in every 2 weeks.