Getting a salon to honor a discount - how do I not screw over my specific stylist?

I got my hair done on Sunday at a new salon that I found on my employer's employee discounts page, under a listed promotion for 20% off your first service. I was extremely happy with my result (a color correction) and plan to return to the salon. However, when I went to check out I mentioned this discount to my stylist (who was lovely and did a fantastic job), and she stated that she was an independent contractor and had never heard of the discount, so I was not able to get it.

I emailed the salon about this, and received this response that puts me in a tricky situation:

"Thank you for reaching out and thank you for trying us at [salon name]. This discount is an older promotion from before my contractors were working at [salon]. No one from [my company] has inquired about this promotion in many years. Were you working with [name] or [name]? (Everyone else at the salon is an employee) I'm currently moving away from independent contractors. What was your total bill? It is a promotional discount for your first service. I can ask my contractors to honor this discount for your second service and if they have issue with this I can either cut you a check out of my own pocket or see to it that you get a discount with an employee of the salon.......whichever you prefer."

I'm in a tough place here...I really don't want to screw over my stylist or take money out of her pocket personally, especially if she is an independent contractor. I would like to return to her specifically for my future color appointments, so I don't like the idea of switching to a non-contracted employee to get the discount. I thought about asking for a haircut with a salon employee to use the discount on, but a simple haircut is much less costly than the 5 hour color correction I had, so I still wouldn't be getting the discount I originally planned on.

Does anyone (especially those who work in the beauty industry) have any advice on how to handle this situation? Any input would be appreciated :) Thank you!