Yes, Dynatrace AppMon DB2 agent support z/os how over the version it supports is 2.1/2.2 for 7.0 and 2.1 to 2.3 for 7.1.
AppMon 2017 - 7.0
AppMon 2018 - 7.1
but it doesn't fetches any OS metrics like Host health information. Please go through the link for more information.