(((They))) will instruct electoral voters to vote Hillary or other republican candidates.
(1). Why must the electoral voters follow (((their))) instructions?
(((They))) are the big potatoes. Electoral voters are mostly politicians, or people wish to pursue a politician career. If not following (((their))) instructions, electoral voters will ruin their own political career and face a much tougher future. However, if following (((their))) instructions, electoral voters will have a bright future (as guaranteed by (((them)))), money, and (((networking))) – that is exactly a politician wants for his/her own future. On the other hand, if Trump gets elected, electors might have to work hard for a better politician career, this is much worse than the future guaranteed future by (((them))). That is, if electors follow (((their))) instructions, the electors will become part of the establishment, and the establishment system gets the electors covered – again, that is, a risk-free, bright politician future (for electors) without having to work hard.
(2). But electors are chosen by the republican party, that means they must be loyal, isn't it?
Well, no, not to Trump. GOP hates Trump. Remember Trump said that he something bad will happen if he did not get the republican nomination? Remember republicans called for trump's drop out for the presidential race? Remember so many republicans, one by one, said he/she will not support trump anymore? Remember GOP got divided when it came to Trump? They don't want to see trump gets elected, especially considering what they did or said about trump (betrayal, unloyal, Bush et al. even supported Hillary). That's it. Many electors will vote Hillary instead as Hillary is the NEO-CON ("true republican value"). While it might be improper for republican electors to vote Hillary, they can vote for another republican other than trump. And this is what (((they))) want – indeed, this will make Hillary president, and it is hard to tell it's rigged because many electors did NOT vote Hillary - they voted another republican, just not Trump. If this shows something, it only means that nobody likes Trump. Hence by doing this, Trump's votes decreases, and eventually lower than Hillary's. If eventually the house of representatives or Congress has to decide, Hillary will get elected since it's determined by (((system))), also because of reason (4).
(3). How are they going to rig the electoral votes?
Many ways. But they need to consider mainly two factors:
(3-i). Is it easy to rig? (force a recount, change the results, add duplicates votes or add votes from non-existed people, etc.)
(3-ii). How many electoral votes they can rig for each red state? (=actual electoral votes number - number of electoral votes they can make faithless)