Can we use the same KMS Host Key (Used for ADBA) and create a KMS Server to meet the need ?
Yes, you can reuse the same host key to install another KMS server:
Can we use the same Domain Controller for both KMS Host & ADBA ?
You have to select one of those method KMS or ADBA when you install volume activation tools:
I recommend you to disable DNS registration for new KMS server to avoid any conflict with ADBA for member servers:
Configure your workgroup server to detect KMS server through registry key :
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