Hello Sawyer,
Sorry to hear of your difficulties. Theoretically, any clear gloss will do the trick, including Future. The idea is that the clear coat will hold the decal together. The trick with Future (or any other water-based acrylic clear) is you must wait at least 24 hours for it to completely cure so it doesn't begin dissolving when you put it in water.
So, apply the clear of your choice, be patient and let it cure completely, trim closely around the decal image, and apply as you would any other decal -- except, as much as possible, avoid manipulating it once it's on the surface. The less you monkey with that fussy decal, the better.
Also, remember that close may be good enough. For example, when decals for an old airliner started breaking up on me I gave them the Future treatment. It helped, but some decals still went goofy on me. However, I found that I could (a) still slide fragments together on the surface, and (b) that Testors insignia blue was nearly an exact match for United blue. So, after the decal dried I was able to smooth some flaws by brushing on a little paint. Feathering the edges of the paint made it less obvious.
Hope that helps -- good luck!
MH
Mark Hembree
Associate editor, FSM