wiring 100A to detached garage
I am wiring a detached garage with 100a service as sub panel from 200a house panel. I am using 2-2-2-4 SE Aluminum cable from the main panel through the basement into the attached garage (in schedule 40 PVC once the cable enters the attached garage, since I am running the cable exposed, i.e. not buried in the wall cavity). I then switch to type W XLPE 4 wire (2 hot, neutral, gnd) in a junction box using aluminum split bolt connectors, wrapped in Scotch 130c, then Scotch super33. This continues out of the attached garage 2ft below grade and into the detached garage (all in sch 40 PVC 2"). Grounding rod at detached garage, ground bar bonded to panel with the included green screw, neutral bar isolated from panel and from ground bar. I need a sanity check on what I have done so far, does this sound correct? I am in process of making final connections.
Also (my main question), where the cable enters the detached garage, the 2" conduit comes through the slab floor where I use a LB box and run the cable inside the wall cavity about 8 feet to the 100a panel. I seem to recall reading something about having to switch the type of cable once it enters the detached structure, i.e. can't use the W XLPE 4 wire cable in the wall cavity? Does this make sense and do I have to switch to a different cable type? Thanks for the help.