Nope, he was right. PDT applies to margin accounts only. Of course settlement becomes an issue. So to answer the OP's question: Use a cash account and daytrade options. Avoids the PDT rule and the problem with settlement.
Another good idea, but then he would have to learn how options work. Once again not the easiest thing to do, and it will require work and a learning curve to succeed at it.
Prop shop is your best bet but remember u will prob have to pay data and platform fees. Just because you have 100K buying power doesn't mean you have to trade 1000 shares at a time!
So I save to 25K then do a few trades then I lose a few go under the 25K rule and I'm back to where I am now Guess you really need 50K to daytrade then way you stay above the 25K rule.