I think it's better and faster to reassemble the hub and remove the freewheel the conventional way. It is a little tricky but not impossible. Glop some grease in there to hold the ball bearings. Doesn't matter if a couple are missing at this point. Be sure to take the springs off the QR first. As noted earlier, google for more detailed instructions.
I've removed a lot of freewheels from hubs with broken axles, and it isn't that big of a deal.
For sure I agree soak it with some penetrant etc. They can be stubborn. People who put freewheels on with insufficient grease should... (deleted...
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