- show us a github repo with source code for this kernel,
- show us boot logs,
- show us SATA performance numbers,
- show us Gigabit Ethernet performance numbers,
- show us how the switch can be configured,
- show us NAT throughput with simple and complex firewall settings
- show us OpenVPN and IPSec encryption throughput numbers
That would be e proof of work and that you think about what this specific device should be used for. Showing instead only some small pictures with a Raspbian Pixel desktop is clearly a sign of stupidity (yeah, it's easy to exchange the rootfs on SD cards but that doesn't tell how smooth things work) 
Ok, to keep it simple for you: show us just the kernel sources for this 'Open Source smart router'. You can't since you don't have the sources since you aren't able to pay MTK for the necessary NDA and even then I doubt you would be able/allowed to release the sources. Please don't lie to customers about 'Open Source' when it's as closed as possible 