Hello Jason,
They short answers is yes, but it needs some additional context. When you are setting up the AWS Lambda functions with multiple GC orgs, please make sure you configure the AWS IAM role's trust policy to recognize each org. For more info please see this documentation.
So yes, you can use the same ARN across multiple instances of GC, but again please remember that each org ID must be included in the trust policy out lined in the documentation above.
Cheers,
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Cameron
Online Community Manager/Moderator
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