If you want to have 2 Master and 2 DB - you need to do enable_ha=false
Also preferably you may want to do 2 webs as well - as web connects to DB.
In Two master 1 will be config master. So the director should be installed to corresponding
Web1 → DB1 ← Master1
---------------------- ^
---------------------- |
---------------------- v
Web2 → DB2 ← Master2
You may want to look at similar question I had when I started my journey with icinga