Betio is indeed overbuilt – from the information and
the graphic, I inferred that these casualties were
from the last action fought on the atoll. The
6th Marines were reserve for both the Tarawa
and Makin landings. I am not sure, but believe
1/6 and 3/6 were committed to finish up on Betio, while
2/6 was assigned the job of securing the other
islets of the Tarawa chain after serving as a blocking
force on Bairiki, an islet next to and ESE of Betio.
The final fight to secure Tarawa took place on 11/28
on Buariki islet. 2/6 suffered 32 KIA (3 officers)
and 59 WIA (1 officer). There were 175 Japanese
KIA and 2 Koreans captured.
Bairiki and Buariki are two different islets, the
latter being at the N end of the chain of islets which
make up the atoll.
Unfortunately, clouds obscure Buariki most of the
time, although a mass vegetation can be made out on
the islet. The USMC AAR (the hyperwar document)
states that 'after several hours of jungle fighting'
main enemy resistance was broken.
No buildings can be seen in the overheads – clouds,
but there are structures noted on the map of the
area, modern structures.
My inference could, of course, be incorrect.