It's a question of reasonable doubt. If his character could reasonably think the mace isn't magic, then he could reasonably decide not to check it out with a rager. Unless it's in his role to be absolutely fastidious about checking such details, he's not really "breaking role" when he declines to check it out.

Of course, if we're talking about some mace that glows, hums, and has runes inscribed all over it...then yeah, I agree it's questionable role-play for a rager app not to get it examined.