It's not up to Intel to do this. OpenELEC 3.2.4 uses a kernel and graphics drivers released before the DN2820FYKH was.
A newer kernel and drivers are available, and the OpenELEC team use these in the nightlies which is why it works. If you want a stable image (with Frodo) that uses a kernel and drivers that support the DN2820FYKH you need to request the OE team to provide one.
Alternatively as it is an open source project you can download the repository, make the changes and build it yourself