UI controls that look similar may have underlying differences, like yours. With certain web UI controls, you have to study the behaviour - for example, using the method SetText may not work, but if you were to click on the control, so it becomes enabled. Then you might be able to use SetText.
It also helps to use the Object Browser, so that you can see the entire objects that make up the UI control.
Also, take note of the date format. You have "MM-DD-YYYY", whereas I use "DD MM YYYY". So you need to get the input correct.
This control has a date range. If I try to enter a date that's not within range, then I get a validation message appearing.
