Windows Server 2012 Datacenter - Cannot activate Hyper-V 2012 Standard edition with AVMA keys

There are a huge number of variations on this problem, but none I can find that exactly match my issue. I am just trying to get VM with Win Server 2012 R2 Standard to activate its AVMA key license against our Datacenter host.

-2012 R2 DataCenter Edition (with 5 cals) installed and activated successfully

-HyperV role installed (among others)

-Server 2012 R2 Standard HyperV instance installed with static IP and Integration Services fully enabled

-Attempted activation provides a success message, but logging shows failure.

Ran the following at an Admin Command Prompt:

slmgr /ipk DBGBW-NPF86-BJVTX-K3WKJ-MTB6V

Error log:

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License Activation (slui.exe) failed with the following error code:

hr=0xC004FD01

Command-line arguments:

RuleId=a5b3220c-2d48-42e8-9733-0374090e4a25;Action=AutoActivate;AppId=55c92734-d682-4d71-983e-d6ec3f16059f;SkuId=f002931d-5536-4908-8d93-40ae584e24d6;NotificationInterval=120;Trigger=UserLogon;SessionId=2

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Not sure what i could be doing wrong at this point.