Since I asked the question, I'll confirm the answer...
2 adult 2 children, POP 6 night w/ 6 hopper park tickets (no water park), dining plan, mid-June
$2785 - Original booking, $200 deposit.
$2424 - At 45 days I called, took the park hopper off (~$200) and asked about 25% off value resort room. The CM gave me the current 15%, I was a day late on the 25%. Balance was paid.
$2190 - Called a few hours after asking this thread. The CM looked up the "kids stay and play free" and said "no problem". I was already paid up, so my card will be credited. I did have to pay a $50 fee to change it because I was within 45 days.
So, it definitely worked. Saved almost $600, which pretty much pays for the dining plan ($60 difference.)
Free dining would have been a great discount and this is nearly that. I'm quite happy.
Funny, we had no thoughts on going to Disney. We had no thoughts on being able to go on vacation for quite a few years yet. I told the family, heck with it, we both work now, we are going somewhere, and priced out a beach trip. Figured it would cost us about $2000. Then I looked up Disney for S&G's and figured out a trip for 4 days would cost us about $2100. Thus, we decided to take the kids to Disney for 4 days. As we looked at stuff, the trip grew until we were at the 6 day mark with dining for the above $2700ish. I didn't want to spend that, but 4 days wouldn't have been enough. Now after 5 months of waiting and planning, the trip is back down to the original $2100 we wanted to spend.