After making exact same configuration as on different pc - same paths, same files, same installation and still being unable to load silent mod I followed the XextFindDisplay I encountered some very old topics about nvidia proprietary driver having issues with linking so preloading libraries was a workaround which in the end fixed my issue.
LD_PRELOAD=/usr/lib32/libXext.so.6 etl
After starting et like that and loading silent mod all libraries were loaded properly:
----- finished R_Init -----
Sys_LoadGameDll -> FS_CL_ExtractFromPakFile(/home/shana/.etlegacy, silent, ui.mp.i386.so)
Sys_LoadDll(/home/shana/.etlegacy/silent/ui.mp.i386.so)... succeeded
Sys_LoadDll(silent/ui) found vmMain function at 0xe9670210
This topic can be marked as solved. Thank you for the help