It seems the OP has made a choice and I expect he'll do fine at the ANA. But I wanted to add some comments about the locations:

FWIW - Chuo Ku covers a large area and it's hard to say which IHG hotel has best access to an office "somewhere" in Chuo Ku.

Chuo Ku does not include Marunouchi and Otemachi. (They're in Chiyoda Ku). Chuo-Ku starts on the East side of the railway tracks that run through Tokyo station. It stretches across Nihonbashi, Ginza and all the way down into the docklands - Tsukiji, Tsukishima, Kachidoki etc.

The JR Yamanote line is convenient for getting to some places in Chuo-Ku, but the Asakusa subway line is better if you're heading to the East side of Chuo Ku. Without knowing the nearest station to his office, it's hard to tell whether a hotel next to a subway station (such as the ANA) would be better or worse than a hotel next to the JR Yamanote line (such as the Strings).

But then, if the OP is being picked up by car, this is a moot point.

IMHO the Intercontinental Tokyo Bay is not so well connected to public transit. It is 10+ minutes walk to the Yamanote line at Hamamatsu-cho. However, if the OP's office were, say, in the lower part of Ginza (near Tsukiji), then the IC Tokyo Bay would be a short cab ride away, which is pretty handy.

Another idea - The Strings by Intercontinental in Shinagawa works pretty well for access to Chuo Ku. It is further away as the crow flies, but the location above Shinagawa station offers easy access to JR Yamanote line (convenient for the Western side of Chuo Ku) and Subway Asakusa line (which takes you through the eastern side of Chuo Ku -- Higashi Ginza, Nihonbashi, Ningyo-cho etc). Gym is small, but open 24 hours a day. But if the OP is being collected by car, then I guess IC Tokyo Bay or ANA Intercontinental Tokyo are closer and better.