In the version at that link (thank you leeneia) they didn't even use D#.** So that's a very good option. Later, once you have the song learned and smooth, it could be fun to to noodle around and see if you want to insert one or more strings from a D# at that spot.

** if you play along with the youtube version, it's a C# because that recording is a whole tone lower than Penny is doing. Which C#BTW calls for the same C or C7 chord formation to slide from home fret 2nd to 3rd.