To any interested readers:
We resolved this in a phone conversation yesterday and here is what we decided:
1. The TEXTING is handled differently than the IM's in print and that will be done in braille too. The IM's are brailled as printed, as a dialog in 1-3 with a blank line before and after. We noted that the IM's are not in double caps and the speakers are shown in the manner of a dialog.
2. The TEXTING is brailled with normal capitalization and is boxed. The occasional narrator comments in lower case is treated as embedded in the texting and enclosed in parenthese. A TN precedes the affected exchange that says non-texting words are enclosed in parentheses in the follow texting exchange.
Double caps are NOT a font attribute and are extremely undesirable in a protracted passage such as this. It was decided NOT to add a font attitribute not present in print and not necessary to understand the material.
The usage of boxes to enclose texting and the fact that the texting is printed in double caps is explained in a TN, probably on the TN page, since this occurs throughout the book. We also noted that the term "texting" must be carefully and consistently used, rather than "text" because text typically refers to the actual text of the book.
Comments from other readers are always welcome.