Yes, in fact you are seeking the 1st Battalion, 141st Infantry Regiment, 36th Infantry Division.
From the date listed, he probably went overseas as a replacement rifleman, and fought in the Southern France campaign, which lasted 15 Aug 44 / 14 Sep 44.
The 36th ID included three Infantry Regiments (141st, 142nd, 143rd), four Artillery Battalions (131st, 132nd,133rd, 156th), plus other elements.
The division landed in North Africa, but was not engaged in combat. It invaded Salerno, Italy 20 Sep 43, and moved on Anzio 22 May 44.
Your grandfather would possibly have been present for the invasion of Southern France in the Raphael-Frejus area 15 Aug 44, with all three IRs engaged.
The division moved up the Rhone River Valley on 21 Aug 44, with the 141st IR engaged in a major encounter at Montelimar 23 Aug 44, in the face of a heavy German counterattack. That attack separated the 141st and 142nd IRs until 27 Aug 44.
Following other significant engagements, the 141st IR was again cut off in the Foret Domaniale de Champ 23 Oct 44, and was rescued by the 442nd IR 30 Oct 44.
There were other activities leading up to the Battle of the Bulge, which according to the information you provided, did not involve your granddad.
In fact, there were three additional campaigns following the Southern France operation: Rhineland, Ardennes-Alsace and Central Europe.
Is it possible that he may have been hospitilized during that period?
Regarding the Discharge
Component: Aus means Army of the United States.
Under Organization: He would have been in the Headquarters Company, 1st. Battalion, 141st Infantry Regiment.
Under Decorations, I would expect that he was also entitled to the Good Conduct award and the American Theater award.
If you will provide the date of departure from the US and date of return, I may be able to give you the names of the ships he sailed on. The dates will be on his separation papers. OK ?