Firestone Complete Auto Care

Good afternoon,
I took my truck to firestone complete auto care in simi valley, CA on 1/2/2021. I asked for and received an oil change, alignment and rotation. I also asked that they grease my Axles using the zerks fittings on the Axles. Instead they chose to grease my aftermarket Upper Control Arms. The only problem is that they used the wrong grease and an improper method. You're supposed to use a silicone or lithium based grease with these polyurethane bushings but they cant tell me if they used a Marine lube or oil based because their guys all use different grease. They also did not loosen the through bolts on the Upper Control Arms which means that the excess pressure forced into the zerks fittings pushed on the already existing silicone based lube which in turn forced the bushings out of their housing and caused a deformation specifically caused them to bulge out. I know this because the manufacturer explicitly states this would happen even with a common grease gun. I'm contacting the manufacturer to get further details and perhaps a demonstration of this to show you. And I also know there was excessive pressure in the housing because the zerks fittings rejected some of the grease they put in which happens when you have excessive grease forced in. I have pictures as well. When I went back to Firestone they told me they would charge me to fix their mistake and that all they could do is loosen the zerks fitting and pressure wash out the lube they put in, but the damage is already done. The bushings are deformed and an oil based lube will eat the polyurethane bushings causing a decrease in elasticity and durability. I have extra bushings from the manufacturer. All I ask is that the grease they used be cleaned out and the new bushings be put on with grease I can provide. I feel this is only fair given the complete disregard for my initial request and the disregard for knowing the proper way to grease this particular equipment without even asking. Also my axles were never even greased. I've been a loyal customer and have come to you guys for all my service needs for both of my vehicles. Please dont ruin that by hanging me out to dry for something your technicians messed up and now fight back to even fix their mistake which would take them a total of an hour and come at no extra cost to you. Thank you for reading this please get back to me as soon as possible.