You cant guarantee that. If there is a GM investigation with 200 accounts that all were raf'ed by the same player and all those accounts are hack farming dungeons. You can bet your ass that the account that sent the raf will get banned.
Have you seen anyone, who hack-farming dungeons to use RAF? Its highly unreasonable. The "hack" farmers do use fraud practices, which do not need any RAF benefits.
But if you are mentioning the common 5man dungeon farmers, or Azyul suicide dungeon farming, this could not be classified as "hack" no matter what, its simply botting
And the GM could have no-single reason to ban legit account, which is not connected to the botting ones in any way:
1. It do not share the same computer or local subnet with the botting ones.
2. It do not have any kind of ingame interaction with the botting accounts, neither with being in same guild, traded ingame, f2f, AH etc., sent/received COD mails with them, being in the friend list, anything!
No point to demonize the Game Masters, the are not emo kids, who do ban people for no reason, when they are in bad mood, they follow strict policies regarding their work, like anyone else!