The NHL is the owners AKA BoGs, they hired Bettman to be commissioner, and he,or anyone else outside of the BoGs have anything to say to an individual owner, on what offer they should or should not take.
Any offer EM gets, is for him to consider or reject.
As far as the struggles the small market teams are having with the rising Salary Cap and the exchange rate and other issues, I'm pretty sure the BoGs/Owners discuss this all the time, as too may weak sisters is not good for the overall health of the league, and that's why I expect a lockout, as soon as September this year.
Also, I don't there are any potential owners, that would come into Ottawa, without doing their due diligence.
"Investing heavily" by a new owner is not going to happen, as they know what revenues the market is capable of generating, and they'd be foolish to squander away their own money, never to see it come back through increased revenues.
I keep going back to this Citizen article, and I know a lot of people want to believe it totally "fake news", but it comes from reliable sources, and reflects on how the Franchise has been run ( on revenues generated) since the owner decided to stop "Floating" the franchise.
Under Eugene Melnyk, Senators have lost $94 million