Hiding native dlls

I've purchased a software SDK that consists of two dlls. The first is a native c++ dll, which can be used with native applications. The second is a managed dll that can be used with managed applications. Most likely it is a wrapper. For a managed application to run correctly one needs the two DLLs. I would like to hide those two from the end user. So far I've managed to merge the managed dll with ILMerge, but that cant be done with the native file. If can't merge that one, maybe I can at least change its name, but then how do I tell the wrapper which dll to look for?