Michael,
Thank you for the sample, your suggestion, and the request for input.
I believe I would do as you suggest, putting the author's comment outside the Nemeth switch indicators required for the spatial problem, with a TN embedded in the author's comment to tell the braille reader what is being referenced. For example,
blah blah blah narrative text blah blah blah ⠸⠩
<spatial probelm transcribed according to Nemeth Code rules>
⠸⠱
What does this number ⠈⠨⠣93 on last line of problem above⠈⠨⠜ tell us? ⠸⠩
<spatial probelm transcribed according to Nemeth Code rules>
⠸⠱
What does this number ⠈⠨⠣10 on first line of problem above⠈⠨⠜ tell us?
Thank you again for the question. I welcome any follow-up or feedback you have.
–Kyle