If a right-click at the split point doesn't offer an UNsplit clip choice, try this...
Copy the edited Sequence 1 clips by selecting them both and pressing <crtl-C>. Now delete those two clips.
Open a new, blank Sequence 2 by clicking the + sign on the sequence tab. Use <ctrl-V> to paste the clips that were copied.
Switch back to Sequence 1 on the timeline and position the cursor at the head of the deleted clips.
Above the bin (top-left) click the Sequences tab. Right-click on Sequence 2 and Place On Sequence at Cursor.

Now it's a single clip.
Alternatively, try programming a TRANSPARENCY effect on the clip to be faded... 
If you make a mistake, repeatedly press <ctrl-Z> to to back, step-by-step.