I'm afraid not. I gave up on the Vegas credit roll, it's prehistoric.
My suggestion would be to create a long ( transparent if you need to ) project in photoshop, say 1920 x 4000 pixels, do all your text layout without any restriction and with all the benefits of a real text editor, save as .png and do a vertical pan automation in vegas.
Yes, I also make my credit rolls outside of Vegas. I use Adobe Illustrator for its exceptional typesetting, ability to insert whatever graphics I want, and total control over every aspect. (Photoshop works, too, but I simply prefer AI's orientation to text.) Pasting in and formatting text from any other document (PDF, text, Word, etc.) is a snap. I export a long AI 'artboard' as a PNG, dump onto the Vegas timeline, and use the Pan tool to pan down the list. Always comes out looking superb.
oidarman, I have my information saved as a text file.
I copy what I want from the text file, open up the credit roll generator, go down to an unused line (it says <INSERT TEXT HERE>, click on it and do a Ctrl+v to paste it in.
If you have any lines that need to have two pieces of information on it (eg. Director & his/her name), make sure that you use the Tab key to get the necessary spacing when you're composing them originally.
Once everything is in the Credit Roll generator, you can go go in and make any necessary adjustments.
Hope this helps.