In Hoteliour theme we prepared special Header Widget Area in Revolution Slider place, which is great to place reservation or any other widget. Reservations widget is available after easyReservations plugin installation in standard WordPress Widgets options. More information about easyReservations Widgets you might get from official plugin documentation.
In WordPress Appearance > Widgets options simply drag and drop widgets into Header Widget Area to display them in header with Revolution Slider.
In Theme Options you can create own header widget areas, and set up width for each of them to make them displayed in header like you want:
Add widgets into prepared Widgets Header Areas in wordpress widgets options Appearance > Widgets: