Received a 1099-r for deceased fIL. Wasn't an IRA, life Insurance, or annuity. Called Company and they said was a taxable "Death Benefit". Only distribution code is 4

Turbo tax deluxe is treating it as an IRA distribution.  I'm thinking there should be another code in box 7 that explains that this is NOT an IRA distribution.  Father-in-law worked for Armoco Steel Union.  Can someone explain why a "Death Benefit" would be taxable?