No, there shouldn't be a game within game. If there is stuff has been copied one directory level too far down. Move up that stuff (overwriting what is in the main game) and likely your game will work.
When replacing the Game folder with the Game folder of the incest patch, i get this:
I'm sorry, but an uncaught exception occurred.
While running game code:
File "renpy/common/00start.rpy", line 273, in script
python:
ScriptError: could not find label 'start'.
-- Full Traceback ------------------------------------------------------------
Full traceback:
File "/private/var/folders/kj/p2qr64n16639510rz_28nfmc0000gn/T/AppTranslocation/36708603-81D1-4D1E-A632-A40660930E73/d/BattleoftheBulges.app/Contents/Resources/autorun/renpy/bootstrap.py", line 313, in bootstrap
renpy.main.main()
File "/private/var/folders/kj/p2qr64n16639510rz_28nfmc0000gn/T/AppTranslocation/36708603-81D1-4D1E-A632-A40660930E73/d/BattleoftheBulges.app/Contents/Resources/autorun/renpy/main.py", line 520, in main
run(restart)
File "/private/var/folders/kj/p2qr64n16639510rz_28nfmc0000gn/T/AppTranslocation/36708603-81D1-4D1E-A632-A40660930E73/d/BattleoftheBulges.app/Contents/Resources/autorun/renpy/main.py", line 139, in run
renpy.execution.run_context(True)
File "/private/var/folders/kj/p2qr64n16639510rz_28nfmc0000gn/T/AppTranslocation/36708603-81D1-4D1E-A632-A40660930E73/d/BattleoftheBulges.app/Contents/Resources/autorun/renpy/execution.py", line 889, in run_context
context.run()
File "renpy/common/00start.rpy", line 273, in script
python:
File "/private/var/folders/kj/p2qr64n16639510rz_28nfmc0000gn/T/AppTranslocation/36708603-81D1-4D1E-A632-A40660930E73/d/BattleoftheBulges.app/Contents/Resources/autorun/renpy/script.py", line 886, in lookup
raise ScriptError("could not find label '%s'." % str(original))
ScriptError: could not find label 'start'.
Darwin-19.4.0-x86_64-i386-64bit
Ren'Py 7.2.0.424
Mon May 11 17:11:53 2020