Slur that encompasses notes from another staff

(Please see attached image)
First, I apologize if this question has already been answered. I do try to search the forum first before posting. I'm self-teaching my self how to play the piano. I came across this slur and maybe I can't find the answer because I'm not sure what the proper name for it is. I searched the internet and the only thing I could find was a "phrasing slur"

I purchased a Christmas duet book that has this slur that includes notes from another staff. When I try to enter the score into Musescore I click on the first "D" note and the command-click the half note "G" and press "S". This creates a slur for just the bottom staff notes. I click the slur and use the elbow links to pull it up over the notes on the staff above. But, that doesn't work. It just widens the gap between the two staffs.

The only way I have found was to turn off "automatic placement" then use the elbow links to draw the slur above the top staff. But...I'm not sure if that's the proper way to do it.

Thanks in advance for any advice.