If I was Disney I'd be incredibly upset if the movie I spent $50 million to make only made $51 million domestically.
I don't think they're incredibly upset, I think moreso Disney executives are just completely confused. And, in addition, a bit disappointed that they are basically back at square one with this franchise unless the case occurs where MMW breaks out huge on home video.
The 2011 Muppets movie was the lightning in a bottle that capitalized on a viral marketing campaign years in the making, and even that fared poorly against the overpopulated competition. Thankfully the film was also a success overseas, and thus MMW was born and IIRC Stoller said that Disney wanted the film as soon as possible. (it was originally set to arrive in the summer of 2013)
Unfortunately that seemed to be too over-ambitious for the script that Bobin and Stoller cooked up, so the film was pushed back nearly a year and Disney failed to push the brand in any huge direction during this time since the overall marketing scheme is, "Trust us, they'll remember. We'll
make them remember."
None of this seemed to work, and audience reaction was tepid at best. I think all the executives right now are just shrugging and going, "Okay, so maybe home video is the ticket here?"
Honestly the box office disappointment happened and now we have to look forward. It's really the only thing anyone can do right now.