Discrete Transfer Function Cannot find state with specified Initial State

I'm a using discrete transfer function block for a filter, and I want to be able to specify the initial state of the simulation using the final state of a previous simulation.

When I try to reuse the previous final state as the initial state for the simulation, I get an error 'Cannot find state # in the given variable'. The variable is indeed part of the final state in the dataset format. However, I only get this error if the model contains a model reference, even when the transfer function is not part of the model reference. If a substitute the reference model for the equivalent atomic subsystem, it all works.

I'm attaching a sample model with a script that shows the problem.

What is happening? What should I check for? How can I avoid this issue?