From what I recall they do take reservations but not on days they are expecting a lot of customers, for example OSU game days. I would definitely call and ask! There is a room in the back that could accommodate a part your size, easily.
I've never had to make reservations but have brought in a birthday cake.
I have never seen them take reservations and we eat their at least once a week. I dont think they would have a problem with bringing in a birthday cake either but I would call them to confirm.
As far as I know they don't take reservations. In sure they would let you bring the cake in.
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