The only issue our lawyer told us that we may have is serving him if we are required to.
IF? I certainly hope the lawyer didn't suggest that there was a possibility that you won't have to serve him. If the lawyer did so, you should look for one who isn't an idiot.
We also know that the money is in a local credit union here in Utah.
Based on one of your follow up posts, it appears that you KNOW no such thing and that this is merely speculation.
Does anyone out there have any idea on the best course of action as to being in Utah and having a partner who ran off with the money to Brazil?
Hire an attorney to file suit in Utah and seek an immediate order freezing the account.
What are the laws as to freezing back accounts?
You can look them up as well as anyone here, and it would serve no useful purpose for you to educate yourself about the details (it would also be WAY beyond the scope of an internet message board).
How do we handle the case if we cant serve Scot?
Serving process on a person outside the U.S. is not a simple process or a good DIY project. Make sure the lawyer you hire understands not only the applicable state law but also the interplay of that law with the applicable international treaties/conventions. I would not waste time with a lawyer who has to ask others how to do this.