Who is responsible, in SCRUM, for making sure UNDONE work is done? (work between your actual DoD and GoLive)

The team is responsible for the work done… They DO negotiate the proper DoD; and which stories are to be included into the sprint backlog.

This would be my understanding:
First of all, depending if your company is acting based on a release train or in a single scrum team on DEV tasks we have the Product Owner or VSE who is in charge of the “content” or the product itself. On the other hand, the Scrum Master is responsible to support the team to bring efficiency and needed spirit/work style in an agile project.
So neither the first nor the second role is fully alone responsible. Why?
Responsible is every Developer or better the whole scrum team.

Now you are talking about the transition, so we have (as far as I understood your question correctly) the product itself fully completed (developed) but it’s not transferred to the production environment (or to the Operations team).

This makes it clear: In an organization (or in any style of organization) you should not implement any method isolated in a single unit. Better would be a company-wide implementation.

As far as this is not the case the Product Owner / VSE has to consider this transition tasks as well and need to define ALL the steps needed to implement it. DoD is therefore not defined in a complete way. But most likely the PO is not the only one to point at. The DEV team should have known as well that there are necessary steps to fulfill (because I would expect the customer spoke about a ready-implemented solution and not about a ready solution in a test environment). Or did the customer spoke about the development only and not about rolling out into production?

So (from my point of view) THE TEAM together is responsible!
In addition -as a suggestion- you may ask yourself if your question is correct ;-)

Hi Konstantin, I do agree with the answers posted.  The spirit of agile is not about finger pointing, but taking joint responsibility for completing a sprint.  If you are too close to go live,  it would also depend on nature and quantum of UNDONE work. The scrum master and Product owner will have to track this UNDONE work to closure and agree to either finish this in the current sprint or add it back to the product backlog, so that it can be taken up in the next sprint.

Thank you all for your opinion. It is very useful to me.

in my humble opinion there should not be any UNDONE work between DOD and go live!
DOD should be stated in a way that if it is met you can go live with the result! In this sense Product Owner is responsible for this: s/he should not accept anything or define Done in a way,  which is not ready to go life. Isn’t this part of a continuous delivery? And the Team may not deliver anything that does not meet DOD.

Everything you mentioned here is true. However imagine yourself a team in the begin of journey. They shouldn’t have DOD as GoLive. In that case read my question again. And what do you think?