I have an opinion (based in part on the extensive correspondence in this string). Murphy's company was formed from Unionists recruited in the area, some of whom were likely more motivated by business opportunities or to avoid Confederate conscription than by patriotism. There is some small irony in the fact that some of the men they fought at Pine Bluff were the hard-core regulars of Cabell's brigade, which had shed similar conscripts in droves after the fight at Devil's Backbone (I wonder if any of Murphy's men numbered among Cabell's deserters?).

Regardless, they were credited with fighting well at Pine Bluff.

And I doubt Murphy was related to the Gov.