Look at the ceiling/floor. OP used 1x width, other used 2x width.
Please look at all the facts before posting something stupid like that again.
It is not stupid, and if anything it is proof.
The screenshots you say that show different bricks being used don't prove anything, they aren't even of the same area of the build. One is focused on the chair and the other is focused on the fireplace.
However, now that I see it, different bricks have been used. They are not identical, but they are still extremely and suspiciously similar.
Also, the OP could just have easily edited some stuff on the build of DaveJason's and slap some other bricks on, as the staircase is a fine example of such.
Or, when he loaded the stolen build on his server he probably did not have all the bricks needed for it, so he replaced the ones that were missing.