Hi Greg
Do they play in the preview? Even if you placed them above each other on the tracks and had them all centered on the screen they should all be visible and play if animated as they have transparent backgrounds.....e.g........

What version of VP are you using? Above is with 8.94. This example exported correctly and played correctly in VLC.
It's an unusual fault as the sequence preview is usually what exports. So... Questions....
Was the Simple text overlay placed on the top track (track 4,) and did you for some reason did you set the text background in the editor to Full background? (Black by default) If so it would cover up the texts below it.
What is the result if you arrange all the texts on their different tracks so as to follow each other (i.e. staggered) and check THAT export. They should play one after another. Do they?
If that fails then pull all the texts down to Track 1 so they follow each other. That export should play.Do they?
Have you perhaps Hidden the Track on output?
Nat