From what I can see at cpu-world, FX-8350 has CPUID of 600F20. Your BIOS doesn't have any such microcode so I changed the existing 600F12 to the latest 600F20 I have from 2016. Here are some pictures:

Before:



After:



Two disclaimers:

a) I don't think there is a reason for it to not work but obviously you take all responsibility
b) I have no Agesa knowledge so I can't help you there

Please report back with a picture which shows the correct microcode been loaded at the CPU with HWInfo or whatever other tool you use

I don't know why it doesn't work at all. It could be Agesa related or lack of such support from ASUS. They seem to provide beta support only for some other FX-8 cpu's, just not 8350. There's probably a reason. The microcode should not be such a problem as Windows can load the proper one while it's loading but Agesa and general support from ASUS is a different story. The replacement was done correctly manually as not even MMTool v3 can detect any microcodes at the image due to AMD's/OEM's lack of standards.