Thank you Joanna! I was thinking of devising something similar, with just the dot 4(s), but will use your technique ... and I have already stressed to this particular student, the importance of reading the Special Symbols page. The author continues to use the prime symbol throughout the text.
Another interesting style she uses ... dropped capitals to indicate grammatical units. See attached. I have decided to include a transcriber note (on the first instance and on the TN page) to include a colon after these dropped letters, in place of the subscript in print. I worded it:
..In print below the unit numbers inside the brackets are subscript in small capital font. A braille colon after each has been added in place of the subscript. Also a braille arrow 1246 25 25 135 is used for a double arrow in print...
Please let me know if I should handle this differently. Thank you!