What Southern Baptists teach
Hell is as central to the Christian mythos as Heaven. Maybe "central" is not the right term, they co-exist as a sort of carrot and stick – arguably for the same purpose, to keep one on the straight and narrow road.
In Baptist specifically, the baptism is a life-changing ritual. You are "saved" or you aren't. There is no grey. You can also get re-baptized.
It is a religion designed for illiterate people. This is not an insult, there is a reason Southern Baptist played well where it did. There is no group reading. Participation is singing familiar hymns. Sermons are emotional and charismatic. Group empathy is re-enforced by songs and prayer which is led by a central "preacher" or "pastor". The communal part is saying "Amen" together at the end. The only scriptures we actually memorized were John 3:16 and maybe the Lord's Prayer – both are considered summaries of the whole gospel. They were learned by rote, not analysis.
The preacher's sermon is structured like a "motivational speech", so natural language, humorous anecdotes, typically not very deep into scripture or biblical lore. It is extremely patriarchal and conservative (compared to other American Christian sects). Women have only soft power so there is often status devotion towards the central charismatic figure (usually the preacher).
God is extremely abstract. Being protestant there are no official depictions of Christ – except they are everywhere, Christ at all ages: baby to resurrection, but in storybooks not up on the alter. Christ is a perfect ideal, and there is no critical separation between philosopher and magician. It is not a cerebral religion, it is feelings.
What Would Pam Do?
I think you have a wide range of options for how Pam might react, however – and this is speaking from experience – Southern Baptists grow up learning about, and understanding the motivations of "The Devil" (this is the name I grew up with in Texas, attending a Southern Baptist church). The Devil is just as likely to start speaking directly to a person – especially un-saved people (which is everyone outside the Baptist faith, including Methodists and Jews and Catholics) – The Devil may be even more likely to speak to these people than an abstract God.
However, she is just as likely to assume her daughter's friend is having a schizophrenic episode, probably depending on her family experience with mental illness. Consider her background, and whether her family had access to medical care, or worked in hospital care, social services, household aide, etc, where they would have encountered people needing care. Her concerns might be religious, but she also might ask a few loaded questions about medication. She could hold both ideas as "true", a religious voice does not exclude a mental health issue.
As a "good" Southern Baptist her reaction would be empathetic, nurturing, and non-judgemental. She would be looking to render care (probably food if she suspects schizophrenia), and she might set aside critical details about the voices, assuming her faith will protect herself, and she should always try to help any one in need, unconditionally. That seems like an extremely good character, but that would be the ideal.
What I would not expect from Pam, would be that she would have any functional knowledge of the Biblical era, or be able to quote from the bible at length. She would not have a strong knowledge of any Old Testament stories, but she might know many stories from the New Testament, but from hearing the sermons not from studying the scriptures.
From your comments, you have a character who is inquisitive, intelligent, and history-oriented. I can't stress enough that these aspects of her personality would not be rewarded by the Southern Baptist community I grew up in. Having personal experience with this sect, I wonder why she did not drift away from this very specific doctrine to a more generically American (non-denominational) version of Christianity. (Americans are consumerist in their selection of religion, unlike most of the rest of the world.)
She seems to be a character who has a deep-rooted faith, who is included to steer the story towards a possible divine interpretation.
But, a Black American Southern Baptist has almost no connection to the Biblical Middle East. Southern Baptists do not focus on scriptures or geographic details of the Bible stories, they are perceived as parables intended to be interpreted into a modern context. Jesus and the The Devil exist today (if they spoke to you, they would not be saying "Thy" and "Thou", they would talk exactly like we talk today). Sermons emphasize the (reductive) "universality" of the Bible's message, potentially at the expense of historical accuracy and critical thinking. A modern slogan like "Jesus Saves!" is more likely than an accurate quote out of the bible.
There is no Southern Baptist equivalent to the seder that teaches history and how to interpret an individual's relationship with their cultural identity. In strong contrast we were scolded for asking too many questions, and debating with an elder was treated as anti-faith rebellion.
Southern Baptist is way more conservative than Baptist, or Christianity in general.