You avoided the question: what if something goes wrong with your in-house process? Is there anything you can do vis-à-vis your employee that you can't do to Google? Is that worth the price of keeping that person on your payroll, drawing benefits, driving up your costs? Would you fire them? Worth the employment claims risk?
These are not binary decisions. People vastly overestimate the value of doing things in-house. Most of the candidates for those "in-house" data management jobs couldn't cut it at Google. Why not leverage Google's HR and recruitment, training, and expertise in infrastructure operations to your benefit, esp. when you consider:
(1) that your own hires offer you no better protection; and
(2) backup solutions are necessarily imperfect.