This snippet merely detects a device based on VID and PID. Actual implementation would require significantly more code and complexity to interact with the device's preloader.
Before fixing it, it helps to know what it is. The Preloader is the very first stage of the bootloader in MediaTek-based smartphones. Its job is to initialize the RAM and prepare the device to load the main operating system. mtk preloader repair tool fixed
If preloader is , you can enter BROM mode (BootROM) which cannot be killed by bad preloader. This snippet merely detects a device based on VID and PID