How much is the DDR4-4600Mhz kit compared to the DDR4-3600Mhz kit? It's highly possible that you're going to enter into the point of diminishing returns, meaning you're spending nearly twice the amount of DDR4-3600MHz but get the same results. There's also the matter of the IMC probably not wanting to go that far into the spectrum with regards to frequency.
What sort of ram kits do you have access to? Perhaps shoot us some links for us to see?
To also add more food for thought;
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The motherboard's specs show that the ram will go to DDR4-4133MHz though please keep in mind that the only way you're getting to that speed is if you pick a ram from the memoryQVL. With that in mind, I'd advise against anything above DDR4-3600MHz.