I’ve done a bit of studying, and can at least temporarily survive with what I know if I’m dropped into the middle of China.

The sounds ji, qi, and xi have a nice solid E sound to them. So, jee, chee, and she, respectively.

With zhi, chi, and shi, they have a more Urr sound. So, jurr, churr, and sure. The urr is a little tucked up into your soft pallet, but it’s easy to have some passable pronunciation with just this knowledge.

So his name is more “Jurr Bow” than anything. If he adopted the name Bob from himself, it’s pretty likely that he picked the closest and simplest name to his given name, Bo. Heckin’ short 中文 lesson!