Hello dm4, the short answer is NO. You need a Microsoft account to redeem the product key and activate the license for your Office setup. As regards to your other question about disconnecting it from your Microsoft account after installing, yes, you CAN sign out of your Office apps after activation, but it's important to call out that some features such as cloud storage or sync settings wouldn't work unless your account is connected. If that's acceptable to you, then, you can absolutely sign out of your Office apps after activation.
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