Audio problem: After the sniper throws down the rifle, we see Captain Stanley start talking to Chet and Marco, though at first we don't hear anything, we then hear, "Put on your air masks, " but that is not Captain Stanley's voice we hear. Oddly enough, to me it sounds like John's voice. Have a listen.
Audio problem: When Roy and Johnny are with the sick dancer at the bar, Roy asks her if she's had anything to drink, and when we hear her say, "No, believe it or not, I don't drink at all, " her mouth says something else.
Answer: I was rewatching a few first season episodes of Charlie's Angels (1976), and in S1xE6 "The Killing Kind," I recognized the same actor. So, to finally fully answer your question, the two baseball players in School Days are played by Rod Perry and Sean Fallon Walsh.
Super Grover ★