For another project of mine, I have been reviewing the individual CSR's of some of the units in this area. Along the way, I found a couple of references to a 2nd corps in the signature line of Colonel Fitzhugh of the 16th Texas cavalry dismounted.
11/22/62-Camp Nelson-2nd bgde-1st Div-2nd Army Corps-Col Fluornoy cdg bgde-McCulloch cdg 1st div-2nd corps
12/1/62 Camp Bayou Meto-Wm Fitzhugh Col 16th Tx-signs for ord stores turned over by him to Capt Pitts ordnance officer 1st Div 2nd Corps TMD
While this may not be conclusive evidence, it does show that at least someone recognized the 2nd Corps as part of the chain of command in November and December 1862.