What else should I do to handle this bad business ethics and potentially illegal behavior by Family Dollar Manager?

Short version;

My friend is a dwarf and needed assistance shopping to reach high items and also because of what you'll see below. So i was with him helping him shop in the store. When we first went in, he purchased a pre-paid cell phone and payment plan, but before the money changed hands, He asked the clerk to help setup the phone, and also asked about whether he could get his money back if it wasn't set up correctly. The clerk said yes to both questions. So my friend paid for the phone and plan, and then while the clerk was setting up the phone he went shopping for more stuff to buy. So maybe 10 or 15 minutes later, after he checked out again, the store manager threw a fit and demanded we both leave even though they didn't set up th ephone. To make matters worse, some plain clothes guy claiming to be security told us to leave, and I know he's supposed to be wearing either company colors or a marked security shirt, and he also had no name tag either. I don't know him from moses. In any case, in the state of Louisiana, a verbal contract is legally binding, especially once money changes hands. They're required by law to hold their end of the verbal agreement they made with my friend. What the heck should I do? I informed the district manager of this and also contacted the State Attorney General's office. I've never broken any law in my life and never once had a business owner demand I leave the store in the middle of a transaction. It's absurd.

What else should I do to handle this bad business ethics and potentially illegal behavior by Family Dollar Manager?
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