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She can create manual Tradeline. One late payment is fine. Do not pull your credit again.
It really depends on the type of loan you're trying to get. 658 isn't an awful score. You may get dinged slightly on your interest rate, but waiting long enough to get your score up to a good spot could mean getting a worse rate down the road due to market rates continuing to climb. Rates have risen nearly 1% in the last 6 months alone. You have to decide if you want to risk taking a higher rate now with your current credit, or gamble on a better/same/worse rate 6-12 months from now.
I'd also consider shopping around without a broker. May be a little more work, but they cant provide the customer service that a lender can. Just my opinion.