I realize this post is a little old but if you are still having problems I would recommend the blender sub-group. The error message is cut off at the most important part but it looks like an issue loading libraries. I would get the latest version of the plugin directly from the github page.
https://github.com/GPUOpen-LibrariesAndSDKs/RadeonProRenderBlenderAddon/releases/tag/v3.6.10
this version is compatible with 4.0 so make sure you are using that blender version in conjunction with this plugin.
Plugins get build based on the applications libraries so its important the plugin was build for the version of blender you are using.