If I understand you correctly…
The two video clips that you’re transitioning between…are they both on one track in the timeline with the transition touching both clips?
Move the first clip up 2 lines to another track. Put the curtain transition on that clip. It will over-lap the 2nd clip that you left on the bottom track, but they won’t touch.
Then but your text on the blank, middle track between the 2 video clips.