The mechanic she's describing is real, though her framing is soft. Take the financing piece first, because it's the load-bearing part of your plan.
Most buyers cannot roll their agent's fee into the mortgage. The fee generally isn't a financeable cost, so a buyer who owes their agent 2.5% has to produce that in cash on top of down payment and closing costs. A buyer at $468k with 5% down is already writing a check near $40k. Adding $11,700 is what actually thins your pool, not agent preference. The workaround the market uses is a seller concession, which the buyer asks for in the offer and which their lender may allow to be applied toward buyer-broker compensation. Concession limits vary by loan program and lender policy, so confirm in writing with the specific lender on the specific deal rather than assuming.
So your $468k listing doesn't avoid the $12k. It converts it into a concession request that arrives with the offer, and now you're negotiating it from a list price you already cut. That's the trap.
On days on market, run it against carrying cost. Debt service, taxes, insurance and utilities on a $480k house is plausibly $3,000 to $3,800 a month depending on your loan. Two extra months erases the entire $12k saving, and softer buyer competition tends to cost you on price too.
Whether you can advertise a general seller concession in the MLS depends on your local MLS's rules, and they differ. Some permit non-agent-specific concessions in the listing, some restrict how it's phrased. Ask your agent for the actual policy text.
Also, she has to get your written approval for whatever compensation is offered to a buyer's agent. Use that form as the negotiation, not the list price.