Ubuntu 19.10 switching monitor to output via Discrete Graphics?

Question

linux

Acer Nitro 5 AN515-42-R3UG
There are 2 video chips Vega 8 and Rx560x. The monitor is output through Vega 8.
For work, there is a need to install a 4k monitor, but the output through Vega does not allow you to run 4k at 60Hz, but only at 30Hz.

~$ sudo cat /sys/kernel/debug/vgaswitcheroo/switch
Gives this output:

0:IGD-Audio: :DynPwr:0000:04:00.1
1:DIS: :DynOff:0000:01:00.0
2:IGD:+:Pwr:0000:04:00.0

I know that switcheroo does not work for AMD.
How can I persuade the system to output an image to an external monitor via Rx560x?