Sean,
If I am understanding your post correctly, are you managing the HORCM/TC pairs for more than one node from a single host? i.e. Does your horcm##.conf on your Database cluster contains entries for LDev's that are from both the DB and application/CFS cluster? (DB Service Groups are global and the application Service Groups are local)
Ideally each Service Group would be configured as global and the would "Switchover" independently of one another with separate HORCM configurations. However, if that is not possible, the coordination between the two clusters would be best served by the remote group agent. In theory you should be able to have the Application Service Group contain a remote SG resource that would verify that your Database and HTC pair status are available before coming online. You would then have to create the same configuration (resource dependency) at your remote site as there would be no concurrency violation protection between the application Service Groups at either site (due to that fact they are Local and not Global).
The all "global" route however is much more ideal.
Joe D