I can't see why the can't open through 270 degrees if the edge at the bottom of the picture is aligned as a continuation of the outside edge of the side panel. The offset should hold the door sufficiently far away to allow the movement you require.
The top hinge wouldn't be a problem as it would fix under the top of the desk but, as you say the doors aren't inset (and the pictures don't show the bottom) you might need a bit of ally angle to provide the horizontal fixing directly under the door, unless there is a variant with a more suitable fixing - might be worth a phone call!
Have a look at the drawings on the PDF of the catalogue page. The 180 degree hinge looks as if it has an even better offset, given that, with your cabinet, the side doesn't protrude forwards like the one in their illustration.