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In practice, no. To ensure distribution of load across their infrastructure, AWS creates an independent mapping of Availability Zone designations (ie: "us-east-1a", "us-east-1d") for each account. Within the same Region, there is no way to guarantee the Availability Zone that you see as "zone A" lives in the same back-end environment as "zone A" seen from a different AWS account. For more information, see the AWS documentation on Regions and Availability Zones.
How can I request a cucloud.net subdomain for use in Route 53?
The process for creating a cucloud.net Hosted Zone in your AWS account and requesting DNS delegation can be found in Route 53 Subdomain Delegation.