Have you tried minks oil or bees wax? What about the waterproofing stuff camping/out door places sell for canvas and boots?
I havent had any issues with my leather Ariats once I have waxed them, and I use something called aussie wax that I found in a leather shop. Its mostly beeswax and leather conditioner. Can't really oil them after you wax them, so dry your boots, oil with neatsfoot really good, and when its dry apply the wax.
Think of it not as a failure but as a success in how not to do it.
Don't look in a horses mouth for a gift.