The PCUSA is apostate, plain and simple.
However, just to be fair... not all conservative, (otherwise)orthodox Christians accept the biblical idea that Jesus satisfied the wrath of God against Man’s sin on calvary. Some, see Jesus death as an ultimate example of selflessness...or, a declaration of victory over sin and the devil (Eastern Orthodox), or Jesus life paying a ransom to free us.... or any of a number of things.
Penal substitutionary atonement is, after all, not the ONLY thing Jesus did on the cross—however, I agree, it is the key legal/forensic work Jesus accomplished there—along with a lot of other things—as the cross was the ultimate human (and divine) achievement, and is of a very mysterious nature.
How do they explain this verse?
“He that believeth on the Son hath everlasting life; but he that believeth not the Son shall not see life; but the wrath of God abideth on him” (John 3:36).
Also, if this particular line is offensive to them, all they need to do is CHANGE the lyrics.