A .ptl version of the model (generated by model._save_for_lite_interpreter())  is need for LiteModuleLoader.load.
Based on the error message, is it possible to regenerate the .ptl model by replacing the class Foo() with class Foo(torch.nn.Module), and resaving the model with model._save_for_lite_interpreter()?
If the pytorch_android:1.9 is still preferred (not recommended because of increased app size and performance regression), one workaround is use the nightly torchvision build 4 and use it as
    implementation fileTree(dir: "libs", include: ["*.jar"])
    implementation 'org.pytorch:pytorch_android:1.9.0'
    implementation(name:'pytorch_android_torchvision-1.9.0, ext:'aar')