You guys are making this far more difficult than it is by refusing to look up stats before typing.
So Joseph is 47th out of the 148 D-men who played 60+ games this year at 5v5 goals P/60.
In terms of the power play, he's 23rd out of 148. Doesn't really mean much, since he only averages 55 seconds of PP time per game.
But yeah, there you have it. If you're looking for more goals from the defense then it has to be done collectively, since they're hard to come by.
The Montreal Canadiens have put up the most goals by a team this season, with 20 scored.
www.statmuse.com
We're 27th in the league at goals from D-men. So it's definitely a problem. That being said, Joseph is not the problem there. Should be looking at Petts, Dumo and Chad, who have 3 goals in 190 games collectively.