How to handle reviewer who is unhappy their recommendation wasn't followed? Inspired by this incident.

The story is a long one, and it’s a bit complicated. The peer reviewer, based at the Max-Planck-Institute for Chemistry, had served as a peer-reviewer for a poorly-handled review process earlier in 2015. He peer reviewed a manuscript and recommended that the paper be resubmitted after it was improved.
The paper went through two rounds of review and re-submit, but each time the paper’s scientific flaws were not addressed.
Next, the peer reviewer recommended that the paper be rejected. Following this, he received no communication from the journal or editor. Later, he discovered that [journal] had published the paper, in its original form, with the flaws unaddressed.
The peer reviewer asked to communicate with the other peer reviewers and the associate editor who accepted the paper for the journal, but [publisher] has so far refused to let him read the other reviews or provide contact information for the others.

(I obscured the name of the journal/publisher since it's irrelevant to the question)
In situations such as this one, should the journal:

Show the reviewer the other reviewers' reviews?
Reveal the identity of the other reviewers and/or associate editor to the reviewer and let them talk? (problem is the other people might not be very interested, since it is drama)
Serve as an intermediary between the reviewer and the other reviewers and/or associate editor while keeping the other people anonymous? (same problem as above)
Do nothing and suck up the reputational damage?

In this specific case, the reviewer has written (same source as above):

I regret that the authors of [paper] (some of who I do know not superficially) lost their reputation in (not only) my eyes subsequently. As to the lead author of [paper], Mr. [name], I cannot call him a scientist, as he betrays fundamental principles of Science.

Which makes me instinctively wary of dragging more people into the argument, but I don't see any other way to satisfy the reviewer.
Related: Why do editors sometimes accept a paper even if a reviewer recommends rejection?
In general, any self-respecting journal would not allow a paper to get published if one of the reviewers has significant concerns about its scientific validity, assuming that reviewer’s competence is not in question.
In the situation you are describing, the journal would have to completely re-examine the decision to accept the paper. This would likely mean appointing a new editor to oversee it and sending it out to additional reviewers, and maybe holding an investigation into the earlier decision-making that led to the decision to accept the paper. If the decision turned out to be erroneous, the journal would issue a retraction.
Of course, if the journal really had those kinds of high standards and leve of integrity that I’m imagining would lead it to act in such a way, this unusual situation would almost certainly not have arisen in the first place. So I think asking “what should the journal do” is a bit moot, since a good journal would not need this sort of advice to begin with, and a bad/predatory journal would not be likely to heed it even if it were offered.