I've asked this before for restaurants like BoG and Ohana during fully booked times. Our last trip we had a party of 9 to accommodate and I found on these boards many people were very wary.
Our experience directly with 2 separate managers on site in restaurant said adding an infant has NEVER been an issue. This is direct from the BoG manager. I asked about fire codes and he said they seat accordingly and rarely to they have to turn anyone away. He also pointed out that several parties of 3 take up the 4 spots so fire codes rarely are an issue. He instructed us to book 4 parties of 2 then when we came he accommodated us.
At 1900PF they told me at the desk that actually they adjust when you have an infant to not a party of 4 but of 3.
Needless to say we have eaten daily at TS over every one of my 6 trips and never have had an issue with adding a person which I generally do as we know people down there and randomly have someone join us at Ohana or BoG. Also my last Akershus I only booked 3 because my DS wasn't on
MDE as a glitch as an infant and it made zero difference. They didn't even blink.