If Google wanted to help, they could skip all this drama by just rendering everything themselves and shipping some Transfer Appliances to the archive.
This it was it says about the rights you give Google by/if you are using their services:
"The rights you grant [to Google] in this license are for the limited purpose of operating, promoting, and improving our Services, and to develop new ones."
The only rubric archival could possibly fall under would be "promotion", but that feels marginal at best.
Seems like whatever legal theory the Internet Archive is using must apply to everyone, including Google, unless Google waived whatever that is.