[Fido969]

molten highly radiating ‘lava’ at the bottom of the nuclear core/fuel rod containers

Now will the reaction stop at that point, or will the fission increase?

[palmer]

Now will the reaction stop at that point, or will the fission increase?

Increase. That's the definition of melt-down, the uncontrolled increase in fission due to the lack of control rods (or any other means of control) of the uranium. But I have seen nothing to indicate there is a melt-down, the highest temperature reading I have heard is 550C which would have to at least double for a meltdown.