ISIS can actually run on rooted roms now. Search it up. People have been running it on the Droid DNA for a bit now. Google isn't the one who is blocking Wallet by choice. Verizon, AT&T, & T-mobile are all on the ISIS bandwagon, and do not allow Google Wallet to run on their network officially . Normally you should be able to use any legal software on your carrier according to the FCC, but Verizon is actually getting around this by not including secure elements in phones but instead moving the secure element to the SIM card which Google Wallet does not check at the moment.
Since I don't have a G2 yet, I can't test the things I would like to. The thread I linked to previously here should give some instructions on how to install Google Wallet from the Play Store and see if it functions. Like i said we may need some lib files though from a Sprint variant. Usually Sprint is the only carrier to support Google Wallet on their devices. Ultimately the VZW G2 may not have an on-board secure element, and we may just be stuck using ISIS unless Google codes Wallet to look for an external SIM SE.