Possibly. But I dunno where else the Luigi Bros. graphics would be stored. Unless it is a NES ROM embedded in the .rpx .
After looking at it in a hex editor:
There are three instances of "nes", but none of them are in all capitals, like they should be. And they don't run in Nestopia.
After looking at it in a hex editor:
There are three instances of "nes", but none of them are in all capitals, like they should be. And they don't run in Nestopia.