Here are the numbers:
Wounded (returned to duty within 72 hrs) - 7350
Wounded (not returned to duty within 72 hrs) - 6770
So there were 6770 who were wounded badly enough to not return within 72 hours. Some of those could be minor lacerations, sprained ankles, broken bones etc. that need more than 72 hours recovery but do not lead to permanent disability.
Their "28,000" sign is not only completely bogus, it erroneously doubles the actual total number of wounded, a number that already includes thousands who had the war equivalent of a paper cut.
I think they are under reporting the number of their "freedom fighter" friends wounded...