Well … I watched what Pipeline.exe was doing with Sysinternals procmon, and it looks like it finds the file ok but still fails to load it. I assume it’s because the image doesn’t match the OS. corflags suggests Pipeline is AnyCPU and dumpbin suggests freetype6.dll is x64 … sheeeesh.
EDIT: ah, it has a dependency on the VC++ runtime for 2012, which isn’t shipped on Windows 10. Installing that fixes the problem.