My husband did a very nice job installing a glass subway tile back splash. I love it!

Unfortunately when it was all complete, one tile cracked a few days later due to pressure from the outlet cover. He realized instantly what he'd done incorrectly, and it shouldn't happen to any other pieces. Question is, can you replace a single tile? Is it worth the risk of damaging others? and how would it be done? I'm sure many people wouldn't really notice it at a a glance, but of course we do.