I'm assuming you were hunting in Pocahontas, correct? That place is big and is FULL of thickets. There are lots of places for deer to hide. I seriously doubt you combed through several square miles of earth, though it may have felt like you covered that much ground. If you did cover several square miles, you couldn't have done it thoroughly, so it's really one or the other.
Anyway, I wish I would have caught your post earlier. I was there on Friday morning and would have helped you look for it then. What part of the park were you in?
Also, you don't have to wait 10 years before you start loading your muzzleloader more quickly; you can start today! What gun are you shooting? Think about this, what is the WORST thing that could happen if you poured a single load of powder down the barrel and it burned up? BTW, this wouldn't happen just because the barrel was warm from a single firing, it's from sparks that could still be in play at the breech. I'm not sure this is an issue with modern inline MLers using 209 primers and BP substitutes, especially something like BH209.
I know I'm gonna get reamed out for this, but I feel like this will help you get over your fear. When you have a sec, take a bit of powder (say 10-20 grains or so) OUTSIDE and put it on a large flat stone, an open pyrex glass, etc...somewhere where the powder is OPEN and will not burn anything flammable (like leaves, your deck, etc), and toss a match on it (or use one of those extended grill lighters, etc). When it ignites, it pretty much acts like a sparkler or a big fuse. As long as you are not compressing the powder and sealing it off, there is no danger of an explosion, etc. So, EVEN IF on the off chance that pouring the powder down a just-fired barrel could cause it to ignite (which will probably never happen to you!), the worst thing that would happen is you might burn your hand a little, which is likely gloved anyway.
What they tell you NOT to do is pour powder into the barrel directly from a FLASK, for several reasons, but the main one is that the powder is SEALED OFF inside the flask, so if the powder going down the barrel ignites, it will travel up the barrel and into your flask, which has now become a BOMB, which will cause your wife to open ketchup bottles for you the rest of you life, assuming you still have a face to feed. Make sense?