Hello, @Stowe, Jim !
It sounds like your Information Security team is primarily concerned about physical security in the data center as well as data residency and data protection. I'd be happy to provide some resources that will strengthen confidence in this decision (and please let me know if you need additional or more specific examples).
Azure Compliance offerings
Azure compliance offerings are a good place to start the conversation as they use well defined specifications to cover common concerns. These offerings provide assurance that your company will meet regulatory compliance standards, including various financial service standards around the world. Microsoft cloud is compliant with more certifications than any other cloud service provider.
https://learn.microsoft.com/en-us/compliance/regulatory/offering-home
Enabling Data Residency and Data Protection in Azure regions
This page has a link to our Enabling Data Residency and Data Protection paper which covers data residency assurances, your control over data, how Microsoft protects data, and privacy regulations and standards. Section IV, "How Microsoft protects access to customer data" on page 23 may be a good place to start.
Azure Datacenter Security
The documentation covers datacenter security in great detail which will provide assurance related to physical, environmental, and infrastructure security as well as other concerns. Datacenter facilities have strict access controls, perimeter fencing, security officers, locked server racks, alarms, video surveillance, and much more.
- https://learn.microsoft.com/en-us/compliance/assurance/assurance-datacenter-security
- https://learn.microsoft.com/en-us/compliance/assurance/assurance-datacenter-physical-access-security
Other options
It may also be worth mentioning that there are networking options that may be able to bring your round trip time down to the low 200ms range by using the Azure network/Microsoft global network or looking at services like ExpressRoute.
- https://learn.microsoft.com/en-us/azure/networking/azure-network-latency
- https://learn.microsoft.com/en-gb/azure/expressroute/expressroute-introduction