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For the nuclear ignorant, such as myself, now that they know where the reactor core is could they not distribute Boron tubes over the active fuel to dampen the nuclear flux and therefore the heat?
I know there are other “control rod” elements capable of absorbing the protons and thereby restricting further splitting of the Uranium. Is it possible to just flood the zone with Silver or another neutron absorber?

No. Boron is a good neutron absorber, and - if dumped as a powder, metal pellets, or liquid over the melted core mass - could absorb neutrons.

But.

A reactor can ONLY go critical if the fuel is pure enough and enriched enough to distribute the enriched U235, U233, or Pu 239 in exactly the right very closely calculated geometry across the width, height, and length of the core with exactly the right amount of moderator material around the fuel to intercept the first free neutron, slow it down by multiple collisions inside the moderator without being absorbed by anything else (previous decay products, previous fission daughter products, oxides, supports, piping or steel or chromium or nickel or concrete or fuel module zirconium and old control rods (hafnium) or reactor internals of any kind) and then survive to be absorbed by an enriched U or Pu nuclei. That nuclei then has to fission, and release more neutrons.

Biggest problem is the core geometry - Wrong shape and it cannot go critical regardless of purity or enrichment or presence of moderator.
Moderators boil off (reason for the melting!) and so - if it is melted fuel, then it can have no moderator (water) around it. If the original core material melted and then was covered by water later - which is likely in many areas - then the melted fuel is the wrong shape to re-absorb enough neutrons before they leave the area or get absorbed.
The fuel concentration and presence of poisons by earlier fission daughter products and control rods melted into the mix at the bottom of the core and down the pipes around the core is the final nail: The heat and decay energy in the radiation comes from the continued decay of the fission daughter products. NO fission daughter product can fission again - it's impossible.

ONLY regions of “clean” enriched fuel can fission hit by slow moderated neutrons - and the melted fuel core are contaminated by too much junk metal to go critical.

Silver is not a usable neutron absorber. Hafnium, boron, and large number of daughter product isotopes do absorb neutrons.