Comparing
output, hidden = model(examples.to(“cpu”), hidden)

and
at::Tensor output = module->forward({indata1, tuple}).toTensor();

you would not expect the .toTensor() on the output to succeed, but you probably have a tuple that you need to unpack. This is why isTensor fails.
Best regards
Thomas
P.S.: While you might have preferred ptrblck to answer, it’s generally preferred to not tag people to not discourage anyone who wants to contribute from chiming in.