The $1109 AOC is how much you get now (before he declares any of the scholarship as taxable). You will get an additional $1116 AOC, if he files an amended return declaring the scholarship taxable.
You do not have to wait for him to actually file the amended return. You can claim the whole credit now and he can amend later.
The kiddie tax should not kick in, but form 8615 will be generated to show the kiddie tax calculation. For the extra $1116 that you get, you son will pay $179 more tax.
