Paintball? Laser tag?
I would stop the "he throws out any suggestions you give". Stop making suggestions. When he comes up with something that is acceptable then plan the party.
If he "doesn't know" then he doesn't get a party. At 12.... he's old enough to figure out what he wants on his own. I don't think this is an "age" thing. My friend has a 13 year old and an 11 year old - both sons. They know exactly what they want. So, if your son doesn't... then work with him on how to figure out what he wants.... not just to reject your suggestions.
You're doing too much of the communciation work. I fast forward this conversation 30 years and I know that his wife will be angry when he "throws out all the suggestions she makes of what to have for dinner but doesn't offer a solution" lol!!!!!!!!
what do you want for dinner? I dunno.
chicken? no, I had chicken yesterday.
steak? no, trying to cut back on red meat.
grilled cheese? no, that's not dinner it's lunch.
well what do you want for dinner? I dunno.