I never actually saw a problem or a question in your post. If your question is if you can access the devices from the head office using ASDM the answer is yes. You just need to enable HTTP access on that interface using the command:
Login to the FXOS chassis manager.
Direct your browser to https://hostname/, and log-in using the user-name and password.
Go to Help > About and check the current version:
Check the current version availa...
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...