Then you are good to go. Just make sure the liquid does not touch anything else except the face plate and the cpu. Be careful the thermal metal is like using mercury when it first comes out of the tip. Don't let it roll off the cpu on to the motherboard. It is electrically conductive. It is corrosive to aluminum too. It comes out liquid and dries as you spread it out. Don't be afraid to spread it, and use a little more to cover more. At first it seems like it isn't sticking to the surfaces but it will dry as you spread it out so take your time. I would wear gloves and use the black q tips provided to spread it you can see it better with those.
There is no mention of Nickel plating. Having installed these coolers, I can confirm that.
The block that holds the Copper Heatpipes is Aluminium. Both metals are a single flush surface exposed to the surface of the CPU's Integrated Heat Spreader (IHS) and the applied thermal compound. There is no Nickel-plating.
Note: The Conductonaut thermal grease must not be used with aluminum coolers!
There's a similar warning on the back of the black zip-lock bag, as well as a red warning label inside the bag.
Note: Conductonaut is a metal alloy and can leave optical residue.
For best long-term performance, we recommend heatsinks with nickel-plated copper floors.
By "floors" they mean coolers which have a nickel-plated solid copper block with heat pipes that are completely contained within the block, NOT direct touch where the copper heatpipes and the aluminum block are a single flush surface exposed to the IHS.
No. It's not ok. And not just for the valid reasons given.
Liquid metal pastes such as Conductonaut are great, even recommended, for use in delidding only. The pastes themselves use an acidic base to keep the paste in a liquid state, which later mostly evaporates. When mixed with copper or aluminium, this causes pitting and corrosion. But more importantly it will void any cpu warranty as the acid will eat the print on the cpu lid, destroying its visible serial codes and identification.
Intel/amd aren't about to honor any warranty on any cpu that is subject to obvious user abuse, and mutilation of the IHS on purpose by use of metal pastes is considered user abuse. It's no different than 'lapping', which is taking uber fine sandpaper and grinding the IHS flatter, to make better contact with the cooler base.