You mean, a Google eBook app that Apple rejected?
Using that logic, Verizon would have to allow any and all apps, by anyone, that were ever rejected by Apple.
The ruling says Verizon "may not block, degrade, or interfere (with downloading a legal app)". It does NOT say that Verizon "must force app stores to approve all apps". That's a HUGE difference.
So if an app is not available from the Apple App Store (which it wouldn't be in that case, since Apple did not approve it), then Verizon is not required to force Apple make it available.
Likewise, if someone wanted to download an app from Cydia to their jailbroken iPhone, Verizon can't stop it. Not that ATT or any iPhone carrier has ever done so anyway. So Google could put their app there.