If you have that access-list on your outside interface and NAT is working correctly, you will not need to specifically allow the traffic in your DMZ interface. The ASA (adaptive security algorithm) will know to let the traffic back in the DMZ interface regardless of what the access-list there says. In fact, even an explicit Deny statement would not stop the traffic.
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...