I wrote up the Delinea Secret Server Cloud security incident situation: https://doublepulsar.com/delinea-has-cloud-security-incident-in-thycotic-secret-server-gaff-581a33990882
As far as I can see Delinea have no responsible disclosure programme or vulnerability reporting contact.
They did, however, do a podcast about how to run one 😬 https://delinea.com/events/podcasts/responsible-disclosure-programs-katie-moussouris-casey-ellis