Wasn't some of his signing business optics at play, too? At the time, landing Burns was a big deal, i.e. getting a guy with a known, well-liked brand to play here and all that comes with that? In addition to the expected on ice results, I think the Rantanen situation is the next iteration of doing it for the overall stature of the business - even if they don't exactly know how to best utilize him within the current roster yet.
I can't imagine they expected quite as much of the will he/won't he sign press and social rumblings to taint his big launch though.