RC toys you are referring to are small, noisy and above all their range is insufficient to give operator a chance in combat environment.
Not to mention anyone with little knowledge in electronics may build a device jamming command frequencies of these things in a few hours.
On top of this, it is not WWII anymore. Killing a modern tank with a grenade is tricky under ideal conditions, let alone then you are using it in such unorthodox fashion.
How would you target your grenade which is not designed in any aerodynamic shape? How would you time detonation?
Given your enemies are deaf and blind it would take hundreds sorties to probably hit a tank with grenade and then it would simply bounce off the armor.
Of course you won’t have a luxury to try it such often in a real battle.
I’m not up on Russian armor, but historically the weak points of tanks have been the rear ends which covered the engine compartment or fuel load. A thermite grenade is essentially a canister, like a soup can. Put some adhesive on the bottom of the grenade so it sticks to whatever it drops on, wire the grenade to the drone so when it drops the pin is pulled. Thermite burns at about 4,000 degrees, more than sufficient to melt through all but the thickest armor. Mostly agree with your points, but that’s the beauty of brainstorming. Ideas pop up. Some of the most effective tactics in previous wars were achieved by “out of the box” thinking. For instance, during WWI a Canadian unit was attacked with gas. A doctor saw the gas cloud coming and suggested that the Canadian soldiers urinate on some cloth and hold it over their faces. The urea in the urine reacted with the chlorine and mostly neutralized the deadly gas, allowing the Canadians to hold their positions and thwart the German attack.