I have experience with this issue from discussions with Mormons, who try to argue that the Bible is incomplete, missing "many plain and precious parts", which they include the epistle to the Laodiceans as an example.
It seems to come from this verse:
Col. 4:16 And when this letter has been read among you, have it also read in the church of the Laodiceans; and see that you also read the letter from Laodicea.
The problem is that this does not mention any "letter TO the Laodiceans". It mentions a letter (unidentified) which they are to get FROM the Laodicean church.
If you look at a Bible map, you will see that Ephesus, Laodicea, and Colossae are all lined up, with Laodicea in the middle. Paul instructed that his letters be circulated among the churches, and so it makes sense to tell the Colossians to send their Letter to Laodicea. And the letter they received from Laodicea would likely be the one they received from Ephesus, namely the book we know as "Ephesians".
Yup. I don't doubt it. I've only been hounding Avery about it because he has a double standard when it comes to his belief that Jerome authored the prologue to the Catholic Epistles.
He argues that it appears in the 6th century manuscript Fuldensis, wherein "Jerome" talks about the Comma being "dropped," and from that Avery says Jerome had Greek mss with the Comma, even though Fuldensis lacks it.
He argues that "Jerome" wrote the prologue in the 1st person.
So, using Avery's own argumentation, he either has to declare Pauline authorship of the Epistle to the Laodiceans or give up Jerome authorship of the Prologue.
The Epistle to the Laodiceans is written in the first person.
It appears in 6th century Fuldensis.
It made its way into Latin, German, and English Bibles for over a millennium.
Furthermore, Jerome rejected the Epistle to the Laodiceans, yet it appears in Fuldensis with the prologue, supposedly written by him.
Avery cannot afford to deal with the Epistle to the Laodiceans honestly because he believes the Comma is genuine, and that errant belief is derived from his errant belief in one pure and perfect Bible.
No Comma, no KJVOism.