The easiest will be to comment (not DD Dummy) the 5 files that you do not need. DD Dummy may bypass rest of files.
//SYS040 dd dsn=File4,disp=shr
//* DD DSN=CA.AT880D
//* DD DSN=CA.AT814D
//* DD DSN=CA.AT814D.P090 etc
Let us know if it worked. I am always interested to hear about IBM mainframe, COBOl, JCL, VSAM, etc