As to the first one, are you sure about the punctuation? If the first sentence is separated it's also a wish for the future. But if there's either a comma or nothing the wish is less clearly expressed, and can be used to mean the same as 'My only concern is that he come[s] home safely. If he does that, I don't care about...'. Sometimes this would be worded as If he only comes back home safe and sound, I don't care.... In fact, that word order is clearer, but I think the example is badly chosen anyway (if your '.' is right).
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