Based on the interop pdf it is unclear if dialing out on the CIX using the other system(in this case Cisco) is supported. here's one of the lines from the interop feature list:
Station CO Line Access
Strata CIX No

But on another line it says the following:
Least Cost Routing
Strata CIX Under investigation
Cisco UC520-16 Under investigation

and also this:
Outgoing Call
Strata CIX Yes
Cisco UC520-16 Yes

Pat Austin
Teleco Inc.
Product Manager/Sales Engineer
Adtran ATSP
TCTE/CTP Certified

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