the first sentence sounds okay to me, although it's a little unusual. I think the second one is incorrect because of the past tense "came" seems out of place. I can't think of a point in time where it would make sense. The first sentence makes sense because you are talking about the present moment (or should be).

Chino: Word to the wise. Be careful on taking advice even from native speakers. We may often not agree on what is right and what is not. I’ll defer to Phil because he may be more schooled in the technical grammar of English than I am. I just go by what sounds right to me. You may wish to double check things now and again with a good English reference guide to be sure of the accuracy of what anyone says. Seems like it would be good to do. Good luck in your studies of English. I wish you well.

The first one means that he has in fact already come (earlier) today. The second one means that he is planning on coming (later on) today. They're both a bit awkwardly worded, but perfectly understandable to native speakers.

Well, Phil, I’m a native (US) English speaker who is 59, and I've been a California lawyer for 29 years. I just don‘t see the distinctions you are drawing in these sentences, so I just have to respectfully disagree.

You may want to check out my post from last week: https://www.italki.com/discussion/164505