Each NHL team gives the NHL schedule maker a list of "available dates" that their arena is available for their franchise to host games. The schedule maker does the best he/she can to accommodate requests made by all teams, such as more or less home games at particular points in the season to avoid conflicts with other pro or college sports ............. but in the end, each team basically have to take what they're given.
The CBA has "mandated" breaks at Christmas, and this relatively new "Bye Week" that the NHLPA negotiated.
It's not like the Senators, or any other team, can decline what is ultimately given them, for their schedule ........... so it's not like the Senators "approved " their schedule, as you seem to believe, perhaps to just have one more thing to blame them for.