No backups should ever be online, you have no control at all over how long the information you store on the cloud will be there, so it is be be assumed that once you upload that information it will be somewhere on the Goggle servers as long as the company keeps existing.

So if I was you I will move my coins from those wallets to a new set of wallets of which the only backup that exist is a psychical one, this is more impractical than your current setup but it is way more secure, and at the end that is all what matters.