You can try to use the RUNRMTCMD in your Job A program.
RUNRMTCMD CMD('/as400dir/scripts/bjk1.csh') +
RMTLOCNAME(UNIXNAME *IP) +
User name and password are case sensitive so you have to use quotes.
Make sure that the user is set up on the Unix side.
Hope this helps!
I’m not sure if it will help you or not, but, the AS400 has a telnet CL command. It’s likely you could add a call to the end of your first job to a program that would telnet in to the unix box, and type the necessary commands, and then disconnect.