I think the focus on ext-ms-win-oobe-query-l1-1-0.dll is a red herring. This is an API set and according to Microsoft's documentation at API set contract names "Names that begin with ext- represent APIs that may not exist on all Windows versions." Furthermore, on my Windows 10 this Api set is indicated as delay load for kernel32 -
This means that the system will not attempt to resolve this at load-time, and its absence should not prevent a dll that depends on kernel32.dll from being loaded. If you think about it, if this was a real problem NOTHING would load in Windows because almost everything has a dependency on kernel32.dll. Consequently, I believe that the problem with your C++ dll is elsewhere.