I don't know CA-7, but I rather doubt it maintains a data base of which jobs use specific data sets. All it will have is knowledge of data sets that, by their existence, can trigger a specific job.
It is extremely difficult for a program - CA-7, for example - to examine JCL and determine the data sets used by the JCL. Consider this JCL, and it is by no means complex.
//PCHECKS JOB (...
// JCLLIB ORDER=(PROD.PROCLIB)
//STEP001 EXEC PRODPROC,LEVEL='01',YEAR=2017,START='450921'
and this member in PROD.PROCLIB.
//PRODPROC PROC LEVEL='?',START='?',YEAR='2017'
//COPY EXEC PGM=IEBGENER
//SYSPRINT DD SYSOUT=*
//SYSUT1 DD DISP=SHR,DSN=FTP.PAYROLL.INPUT
//SYSUT2 DD DISP=(,CATLG),UNIT=STSDA,SPACE=(CYL,(20,5),RLSE),
// DSN=PROD.PAYROLL.Y&YEAR...WEEK&LEVEL.(+1)
//SYSIN DD DUMMY
//GENCHKS EXEC PGM=CHECKS,PARM='&START'
//CHECKS DD SYSOUT=(P,,CHKX)
//INPUT DD DISP=OLD,DSN=*.COPY.SYSUT2
FTP.PAYROLL.INPUT is pretty simple, but PROD.PAYROLL.Y&YEAR..WEEK&LEVEL.(+1) has the substitutions, and the GDG, so the data set is not really resolved until the job runs.
The trigger data set is FTP.PAYROLL.INPUT.