Ad Hoc Immunizing Hypothesis and Peer Review: To what extent do they correlate?

An ad hoc immunizing hypothesis is "an escape hatch or loophole that defenders of a theory use to protect their theory from falsification" (Lillenfield, 2010c), in accordance with our textbook. An online article similarly states that this type of hypothesis "is one created to explain away facts that seem to refute one's belief or theory" (Carroll, 1994-2010c). A link to this article is available to you here:

No matter how one phrases the definition of an ad hoc immunizing hypothesis, we can agree that this hypothesis explains how scientists may defend a theory of theirs. When one creates a theory backed up by experimental data, one defends their theory using peer review. What I wonder about is whether the peer review fraction of an experiment is truly valid or not; when one receives peer review, the public needs to consider how that was done. How do we know as outsiders that the peer review was done by people who were not biased; do we know that the peers reviewing the experiment were not closely involved with the scientist(s) conducting the experiment? Perhaps the peer reviewers were already effected by the ad hoc immunizing hypothesis themselves prior to reviewing this experiment? Maybe the reviewers were already supporters of the theory being evaluated before reviewing an experiment; perhaps they are biased themselves!

In one fictional example, perhaps a pseudoscientific book is released regarding a new method of self-medication using natural herbs. The book claims that two other scientists have backed up the claim by conducting experiments on patients that used the medication to heal themselves. Here is where we must question the peer review: who were the two "other scientists"? What type(s) of experiment(s) did they perform, and how many subjects did they use in their experiment? One must factor in these questions when reviewing the validity of a claim. Thus, I wonder how little information one can accept in order to believe a hypothesis as valid, while also considering the ad hoc immunizing hypothesis.