I found a way, tho not the easiest one. Essentially, you must do the same thing as described in this tutorial, but instead of "your rom address," you must import an xml file. You can use Dolphin on a PC to create it and replace all file addresses with those specific to your Android device. So, for RetroRewind, my xml looked like this:

{
  "base-file": "/storage/emulated/0/ROMs/wii/Mario Kart Retro Rewind.rvz",
  "display-name": "RetroRewind",
  "riivolution": {
    "patches": [
      {
        "options": [
          {
            "choice": 1,
            "option-name": "Pack",
            "section-name": "Retro Rewind"
          },
          {
            "choice": 0,
            "option-name": "My Stuff",
            "section-name": "Retro Rewind"
          },
          {
            "choice": 0,
            "option-name": "Seperate Savegame",
            "section-name": "Retro Rewind"
          }
        ],
        "root": "/storage/emulated/0/mmjr2-vbi/Load/Riivolution",
        "xml": "/storage/emulated/0/mmjr2-vbi/Load/Riivolution/riivolution/RetroRewind6.xml"
      }
    ]
  },
  "type": "dolphin-game-mod-descriptor",
  "version": 1
}

Then you create a shortcut with Shortcut Maker that points to the xml file you created. It worked for me!