Fraudulently damaging by Servify India

I gave them my iPhone Xs for servicing/ repairing, there was a problem with 3D touch and nothing else. The rest of the device was working perfectly good. I had taken a video of the device before submitting where it showed a white strip that indicates no water damage is done, as soon as it reached there, they diagnose water damage and show me the photo of the white strip turned red which indicates that it was water damaged. As soon as I came to know about it, I told them that it cannot be possible because my phone was never in contact with water and iPhone being IP67 water-resistant, it just cannot be possible. They also send me a diagnostic report. showing that there was a problem with my speaker and mic and some various other component and told me that they will replace the device for a huge amount. I denied this request and asked them to send my device back. As soon as I get the device, I take the video of the same spot which was white before sending it for servicing and turns out that it had turned red. This means that they tampered with my device which was working perfectly fine. I also get a diagnosis done online from Apple (authorized/ official support) and turns out that there was no problem with the microphone and the speaker and everything was completely fine. The tampering done by them has caused me to lose my warranty and now I cannot get my servicing done from Apple due to breach in warranty because of Servify. Also, it has been confirmed by Apple that Servify is not authorised by Apple to provide service but Servify falsely claims they they are authorised service providers. Can I file a case against Servify and how much compensation can I ask them for?