Just the luck of the draw really Uluru, you either only do races that have on the day entry, or you accept that occasionally you'll pay for a race and miss it.
I've missed 2 half marathons I'd entered through illness and injury before. Disappointing, but just one of those things.
Sounds like you're wise to not consider running it.
If you can find someone to sell/pass the place to, the organiser may well let you swap their details over, but clearly that's just at their individual discretion. They don't want 100s of people adding to their already overflowing workload!