He looks like a giant! I would agree with setting up mock scrapes, but make sure you do it right.
I would recommend spending a little extra money and getting a good quality urine, not some knock-off fake stuff, a mature Buck will catch on to that real quick and you may blow your chance. Make sure you wear rubber/latex gloves when you go out to set them up and do it early afternoon when the buck should be bedded. I would recommend setting up 3 scrapes around your stand; 1 to the left, 1 straight in front of you, and 1 to your right, all about 15-20 yards out. And don't pour a gallon of urine into the scrape you only need a few drops and then place a few drops onto a licking branch directly above the scrape. When that bucks comes in to hit those scrapes he should hit all 3 of them and no matter what order he hits
them in he should present you a shot. Also I wouldn't think that he ran all of the other bucks off on your property, maybe just in his core area. How big of a piece of land are you hunting? On top of him hitting up those scrapes the scent will draw in other bucks who are cruising around. And in my opinion as far as the grunt call goes, I like to use mine as well but if you grunt at him and he starts to act wearry or funny, stop. You don't want to scare him off cuz he light not return for a couple days or maybe even weeks. But anyways best of luck to you harvesting him and keep us posted!