I doubt it's a bug b'cos ONTAP Simulator always provides 2nd Node licenses for both non-esx (vmplayer,vmware workstaion etc.) and esx build.
In the licenses.txt file, there is a separate license for ESX and non-esx build and then there is a common licenses which could be used for both esx or non-esx 2 node simulator cluster.
This is the section I am refering to:
Licenses for the second node in a cluster (Serial Number 4034389062)
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Use these licenses with the second simulator in a cluster (either the ESX or non-ESX build).
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Could you please confirm if you added both set of licenses to the cluster, i.e one given in the esx section and one from non-esx build section?