Hes asking if the DDGM is the Master of a Lodge and a DDGM official visit must happen with his own lodge who would sit as master to open the lodge?
My thought is that if that happened he would just open, then do his ddgm stuff and then go about with reg business. However i doubt someone would accept the WM position if they were or were going to be a DDGM
Under GLoTX, the Lodge & GL years are offset by about 6 months. Here a DDGM must be a Past Master. On more than a few occasions, a second-time-around WM has gotten installed in June/July, and then has been appointed DDGM in December, thus serving as both for about half a year. Generally such a Brother has taken the WM job @ the behest of his Lodge, not knowing that he was being considered for DDGM.
To the operational question proposed, the proper procedure in the instance of an official visit would be for the DDGM to arrange
beforehand for one of the PMs of the Lodge to open & preside over the Lodge so that he may concentrate on performing his DDGM duties.