Command not found: pdebuild fails, fakeroot succeeds

I'm updating a debian package and I need to call an external build dependency which is actually a toolchain. It doesn't have a deb package so I can't provide Build-Depends. I've chosen to include it in the source archive instead, and am calling ndk-build which then calls various tools e.g. arm-linux-androideabi-gcc which reside in a toolchains folder within the bundle. When I reference this in debian/rules: override_dh_auto_build-arch I am using $(CURDIR) which resolves to /build/pkgname-1.0. It succeeds when running fakeroot debian/rules build, but not when I run the whole process using pdebuild. I get the following output when building for i386: make: Entering directory '/build/pkgname-1.0' NDK_PROJECT_PATH=/build/pkgname-1.0/android/ /build/pkgname-1.0/android-ndk-r12/ndk-build make: Entering directory '/build/pkgname-1.0' [armeabi-v7a] Compile thumb : dpfp <= dpfp.c make: /build/pkgname-1.0/android-ndk-r12/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86/bin/arm-linux-androideabi-gcc: Command not found /build/pkgname-1.0/android-ndk-r12/build/core/build-binary.mk:472: recipe for target '/build/pkgname-1.0/android//obj/local/armeabi-v7a/objs/dpfp/__/__/examples/dpfp.o' failed make: *** [/build/pkgname-1.0/android//obj/local/armeabi-v7a/objs/dpfp/__/__/examples/dpfp.o] Error 127 make: Leaving directory '/build/pkgname-1.0' Is this a chroot pathing issue? The files definitely exist in the folder shown as I have added ls -R when troubleshooting and I can see: /build/pkgname-1.0/android-ndk-r12/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86/bin: arm-linux-androideabi-gcc I've tried adding the folder to PATH, calling sh ndk-build, explicitly moving the bundle folder to $(CURDIR) but nothing seems to work.