He would have been able to print the posters, but had he only raised 10,000, he would still be in the hole for:

Less shipping supplies ($5,811)

Less storage lease for 5 months ($690)

Less postage ($4,701)

Less temporary help ($741)

Less charity: water contribution ($2,000)

$13,943 in addition to his $15,000 loan, as well as Kickstarter taking 5% and the 5% merchant fee, which would have come out to ~$1000. I don't think people would have received the poster.