My son was fired from his job and now his employer is trying to appeal his unemployment claim.?

I am MA & son - a laborer for a concrete co., , there 5 years, no issues, gets laid off in the winter...about a month ago, my son had leave work at 5 after working all day - had an appt. to fix ...his boss/owner of co. had a fit!!! And this guy is a real character I must say, and his rage/words to my son- you wouldn't say them to a snake...my son left now upset after this scene...and that was the last this guy called him to work. A month previous to this incident - work was slow..he was laid off all September (did get benefits), and worked sporadically in October, then this. He called unemployment- they called the owner - that never responded to the claim - so his claim was approved. Now he has filed an appeal...I'm intelligent articulate person, paralegal and VP w/ financial co., registered with the Securities and Exchange Commission..I want to help my son..this is not right..does this jerk have any shot of denying his unemployment claim?