I have a few routines in ^rINDEX that are missing in ^ROUTINE. At least some of those routines lack a timestamp, probably Date and Time Modified in ^rINDEX. It causes D %RO crash when such a routine is referenced by a routine range, since "" is an illegal $ZDTH value.
Healthy entry (note the timestamp): ^rINDEX("ABC,"INT") = $lb("2021-06-15 15:08:38.846885",) ;The second argument is sometimes present and sometimes not, likely the routine size.
Unhealthy entry (note an empty timestamp): ^rINDEX("DEF,"INT") = $lb("",21)