this still fails and the solution works on 4.17.1
#elif PLATFORM_LINUX
FString CmdExe = TEXT("/bin/bash");
FString ScriptPath = FPaths::ConvertRelativePathToFull(FPaths::EngineDir() / TEXT("Build/BatchFiles/Linux/RunMono.sh"));
FString IPPPath = FPaths::ConvertRelativePathToFull(FPaths::EngineDir() / TEXT("Binaries/DotNET/IOS/IPhonePackager.exe"));
FString CommandLine = FString::Printf(TEXT("\"%s\" \"%s\" certificates Engine -bundlename \"%s\""), *ScriptPath, *IPPPath, *(BundleIdentifier));