So I know this thread is old, but I wanted to say that I hope your son had a good Boys Night Out.
We experienced something similar about a year ago. My now 4 year old daughter has special needs. She has microcephaly, complex partial seizures and an undiagnosed genetic condition. Her overall development is that of a 2 year old. Developmentally, she's behind her 2.5 year old brother.
We attend a playgroup and I sent out invitations for her third birthday party. It's so difficult because I plan her birthday parties around her developmental age and not chronological age. What other kids her age might be able to enjoy and do, she does not because she's not there yet. So, I booked two hours at an indoor playground thinking that was the perfect "inbetween".
Of 15 kids invited, only three responded. Two of them said they weren't coming. 12 kids ignored the invitation.
My heart broke. It felt worse for me than it did for my daughter. She didn't understand, thankfully, and I dread the day that she wants to have a birthday party and can understand it when kids don't respond or don't show up. I don't want to have to face the questions.
I didn't care that I was out $300 for a cake and private booking of a playground and couldn't get my money back. I was heartbroken that this was a small glimpse of what may come in the future.