The resource DOI field in the item form allows you to put in any DOI and does not check if the DOI resolves to anything. It might be the right choice not to verify the DOI at this stage as someone may forget to update their item when the resource DOI is minted in the future.
It looks inelegant though for the published version of the item to have a link (on the right) that doesn't resolve when someone clicks on it.
I suggest that the resolution of the DOI is verified before a hyperlink is shown to the public.
One of the first things we're looking at after the FOR code migration is references and links, so this is good timing. I will add this to the conversation.