Removing M1 Abrams tag... they don't have that kind of slope on the turret, that's a British style, body's a little off too....

How long did it take them to dig that 33 foot hole for the mobilesuit to stand in?

And what was the point? It's not like a robot sticking 25 feet out of the ground in the middle of an open plain is much more subtle than it standing completely out of the ground.

Maybe they used the robots to dig it.

That tank looks like an Leopard 2

Yep - the turret cheek armor, 6/2 smoke grenade launcher setup, and turret bustle rack for track ice cleats all look like those of a Danish Leopard 2A5DK.