The problem with the loaded dice solution is then that it isn't a solution -- it is a crutch. The difference between a solution and a crutch is that with a solution the problem is solved, but with a crutch, the problem is worked around but remains. The RNG is like a leaking pipe and the loaded die crutch is a bucket placed under it instead of fixing the pipe. If they said that hey this is a short time measure because rewriting the RNG is a big procedure and will take time, that would be fine. But if this is their long time "solution"... well, it doesn't solve anything.
Wouldn't "solving RNG" mean changing the system? If the system is "roll 20", there is nothing you can do to improve it outside changing the rules or loading the dice. Or you can cheat without telling the player as many games do - not allowing to roll low many times in the row, forcing a good roll if it didn't happen in a while etc. I would rather get a system which works in the way it tells you to do, buy I won't argue that just rolling d20 is not a good system. It ain't good here, it ain't good in Kingmaker.