The term "Near Pine Bluff" often refers to soldiers camped at Sulphur Springs which was about 9 miles from the Jefferson County Courthouse.
I base some of my conclusions upon the fact that three of these Companies, McSwine's, Yell and I believe Hallidays, were "mustered in" at Pine Bluff according to the Muster Roll records by a Major Greenwood on May 12th, 1862. By the way, Captain Fountain Pitts Yell was the son of major general James Yell of Pine Bluff who was the commander of all the Arkansas Militia.
Yells company was enlisted at Monticello, as was Hallidays at Centerville, present day Rowell, Ar., in Cleveland County. As you know there is always some confusion between the enlistment date and the dates that a Company, in this case, was accepted into service. The latter date of acceptance is the Muster date when they are sworn in by a repersentative, usually an Officer, in this case Major Greenwood, of the Government.
That Officer as best I can find out was at Pine Bluff and was not present at Monticello, or Centerville since it would have been impossible for him to have rode to all three places in one day and swear in each company seperately.