We have encountered this as well. RDT 9.1 uses COBOL V 5.1 which requires new work files. When using Rdz you will also need to change the ELA* procs.
Here an example that should work:
//EXPRESC JOB ,
// MSGCLASS=H,MSGLEVEL=(1,1),TIME=(,4),REGION=0M,COND=(16,LT)
//*
//* Replace below with the COBOL member name
// SET MEM=EXPREVAL
//*
//* ------------ COMPILE --------------
//COBOL EXEC PGM=IGYCRCTL,REGION=0M,
// PARM=('TEST,LIST')
//STEPLIB DD DISP=SHR,DSN=IGY510.SIGYCOMP
// DD DISP=SHR,DSN=FEK910.SFEKAUTH
//SYSIN DD DISP=SHR,DSN=EMPOT.ZPICL.COBOL(&MEM.)
//SYSLIN DD DISP=SHR,DSN=EMPOT.ZPICL.OBJ(&MEM.)
//SYSPRINT DD DISP=SHR,DSN=EMPOT.ZPICL.LISTING(&MEM.)
//SYSMDECK DD UNIT=SYSALLDA,SPACE=(CYL,(2,3))
//SYSUT1 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT2 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT3 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT4 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT5 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT6 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT7 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT8 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT9 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT10 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT11 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT12 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT13 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT14 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//SYSUT15 DD UNIT=SYSDA,SPACE=(CYL,(1,1))
//*
//*---------------- LKED -------------------
RDzJohn
RDzJohn