You can figure out the checks and make your own patches to Qemu.

https://github.com/SafeExamBrowser/seb-win-refactoring/blob/cb84fbd689493a0486b0f4373ab98674afd2b38e/SafeExamBrowser.SystemComponents/VirtualMachineDetector.cs

I managed to get mine working.

Edit: SEB now checks for browser integrity so this is no longer relevant.