I played around with this a little bit. Please understand that I'm not very experienced with these puzzles, so someone else may have better advice for you.
Specifically, I tried to solve the word or phrase associated with the block containing the apostrophe. I took all 16 possible delimitation sequences for the letters, and Caesarian shifted them. No luck. I then used the same procedure after reversing the block, inverting the block, (dashes to dots, and dots to dashes), and doing both. Still nothing.
The closest that I came to finding anything that worked with the apostrophe was, when using the block in its original order and reversing it AFTER un-Morseing it, I came up with R'W. This can be Caesarian shifted into I'D. It's a possible start, anyway.