There is no exit ramp on the issue of impoundment, because Trump will never agree to it, and he has control of the facts on the ground. The only possible resolution of the issue will come through litigation. That is why impoundment is not the centerpiece of the blue team’s demands in spite of its extreme constitutional significance.
As to the Biden Obamacare subsidies, we have not yet heard the roar of anger in response to massive increases in insurance premiums because most Americans are not aware of them yet. That will change in a few weeks. If the public response doesn’t force the GOP into a meaningful compromise at that point, the only possible end to the shutdown will be a deal that saves the face of the Democrats, but nothing more.