I got it working on Solus by installing the contents of the deb package manually. If anyone's interested you can find the instructions below. I've tested this with HDX RealTime Media Engine 2.8 and Citrix Workspace 1906.
Before starting make sure no Citrix instance is open.
Download and extract HDX RealTime Media Engine package from Citrix
curl -s -O https://downloads.citrix.com/11922/HDX_RealTime_Media_Engine_2.8_for_Linux_x64.zip
Extract deb package and the contained tarballs
ar -xv HDX_RealTime_Media_Engine_2.8_for_Linux_x64/x86_64/citrix-hdx-realtime-media-engine_2.8.0-2235_amd64.deb
tar -xvf control.tar.gz
tar -xvf data.tar.xz
Copy data-files (from data.tar.xz) and run
postinst script (from control.tar.xz)
sudo mkdir /usr/local/bin
sudo mv ./usr/local/bin/* /usr/local/bin/
sudo ./postinst configure
After that you probably also need to set
AllowAudioInput=True inside your