Asus GSTRIX 16 2023, LM replacement or PTM7950?

As it is, I plan to replace the thermal paste application on my G Strix, went to the Asus service center, and they stubbornly told me that I cannot use any other type of paste for the G Strix as it could damage it. Having used PTM7950 before in the past with my old laptop, and seeing the posts here of some people using PTM7950 instead of replacing it with LM. Feel like they're just charging me extra with the LM replacement. Since when I suggested PTM7950, they said if it gets damaged it's my fault.