Bluetooth and Zigbee on Linksys EA8300

The Linksys EA8300 is based on the Qualcomm IPQ4019 and already supported by openwrt.
Why is Bluetooth currently not supported?
How could I patch bluetooth support?

How could I add support for the SiLabs EFR32MG radio?
I assume it's using some Gpio pins or i2c, as it doesn't show using lsusb or lspci.

Any Ideas where to look?
any Idea where to get sources for the OEM Firmware?

I'm quite interested in this. Where did you see that the EA8300 has an EFR32? I looked through the FCC teardown of this router, and couldn't find such a chip, but I may have missed it...