I ran across this annotation with an arrow (and lines) and I'm not sure how to handle it. Could you suggest something? I thought about a music asterisk preceding the interval sign, but I'm not sure that would make sense here. (And what about the horizontal lines? Are those musically significant?)
In situations like these the transcriber's note will be your best friend. I would put a note before the music begins saying something to the effect of "There is a downward pointing arrow above the first chord in the left hand."
And yes, the straight lines connect the tenor line, where the "sol" pedal tone is occurring, as per the text. This information could be added to the transcriber's note before the music begins. I'm assuming you'll place the text that is printed between the staves before the music, as well.... so your TN could follow that information.
My rule of thumb is that if the annotations are going to gunk up the braille music and make it difficult to read, remove the annotation and describe it in a tn either before the music or put in a footnote.