I think you are right. The market tends to over react to any piece of bad news in the data center space. One tenant default does not reflect a bad strategy. They do have some big rent roll-downs on renewal coming up that are also placing pressure on the stock but I think those were priced into the valuation before the default news,
The UBS analyst has had a negative view of DLR for many years. His price target a couple of years ago was about $45. Creates a self fulfilling price drop when he takes a public negative view. Very beneficial for UBS' hedge fund clients who are short(?).
Nice idea. Don't know why they would split, though. These data center stocks are so volatile based on mis-information. Good idea to take profits in one and re-invest in another (like CONE or EQIX when it's off) and ride up again.