The Grand Staircase is now a big hole. The Radio Room was far closer to the bridge than the staircase. They are after the safes from the First Class Purser's Office that was just to the side of the staircase.
Funny thing, I had stumbled across a forum re TITANIC before. Seems a Purser of Irish descent got the rich folk to lock up their valuables in the safes. Thus far only the Second class Purser's safe from C Deck has been recovered. The First Class safes, as in plural, safes, remain in the wreckage. Why would they request to cut into the wreck near the Grand Staircase when that area is easily accessed now and NOT where the "wireless" room was located. Now, for those that can dig better: When was the first wireless telegraph machine installed on a ship? I'm going with after 1912. The radio operators would've been taking down messages with a pad and pencil.