So, I was thinking of dilling holes in my pedalboard so my cables could go under and it would be a lot neater. I drilled the first hole without thinking, and since the cables have 90 degree jacks, they can't fit through the holes, and they would have to be pretty giant holes if they could fir in. Would cutting the wire, putting it in place, then soldering it back together be a good idea? It better be, because I've already cut the wire in a big rush of stupidity .

BTW, I've fixed up guitar cables in th past, but this patch cable has (when cut dead in the middle of the wire) an outer conductor (I know that's the ring), but has 2 centre insulated wires. The lead is definately mono though, so, I don't know...
I make my own patch cables and it's really a breeze. I don't know where you cut it, but I'd recommend getting a new plug for it. My local electronic shop sells the low-profile, right angle ones for $0.50 a pop. They're really easy to install, you just unscrew the back, solder the inner wire to the tip and the outer wire to the casing.

As far as fixing the one you already have, it's a PIA to fix a shielded cable, but it can be done. Solder your inner connector first, tape it up, or use heat shrink, then twist your outer connector so it's like a regular wire, and solder them together, then tape up the whole thing.
MG Free At Last
If you're going to route cables under your pedalboard, it would be best to invest in patch cables you can build yourself. George L's makes a pedalboard wiring kit that can make 5 cables for $59, and it's a great kit. The plugs don't have the full end on them, so they can make those bends easily, and they're solderless plugs, so if you need to re-route, just unscrew the plug and drop the cable out.

It's worth the investment...other than that, you're pretty much screwed if you just went all willy-nilly and cut the cable in the middle without thinking things through.