After digging more into it tonight, i am more convinced that it is the front driveshaft splines.

Is it normal for the transfer case splines to wear down before the driveshaft splines do? I can see no wear on the drive shaft splines but I can see indentations on the TC splines.

since the OEM shaft only engaged the TC splines by about an inch, would that new 1" longer shaft from cobra be enough to engage the untouched part of the TC splines?