It seems that the pcscd already created 200 thread and pcsc-lite library do not allow client to create more thread.
Smart card redirection on Linux client was based on the pcsc-lite. Could you please double check the pcsc-lite library version both on your ThinClient and RHEL by using the command "/usr/sbin/pcscd --version" ?
In order to get more log info from pcscd, Please try the command: "sudo pcscd --foreground --debug --apdu --color | tee log.txt".
Wish you can find more clue of why pcscd not work as expected.
