Which version of Linux are you using?
Can you try installing xinerama? On some platforms, this will fix the issue. Specifically, this fixed that issue on Ubuntu 16.04.
sudo apt-get install -y libxcb-xinerama0
For BrainSuite21a, the version of Matlab Runtime to use is 19b. Direct link: https://ssd.mathworks.com/supportfiles/downloads/R2019b/Release/3/deployment_files/installer/complete/glnxa64/MATLAB_Runtime_R2019b_Update_3_glnxa64.zip
That isn’t causing the launch problem, but it is necessary to run some of the programs in BrainSuite.
Let us know if that fixes the problem — if not we can get some further information and help you resolve this.