I'm so glad to hear that Snoopy's test results are fine. Hopefully you'll be able to find out why she's peeing outside of the litterbox.

Do you have covered litterboxes? If so she may prefer to use one that's uncovered. I know it sounds weird but my Starr prefers to use uncovered litterboxes because he's claustrophobic and afraid that others will surround him while he's using the litterbox. I learned about this from a pet pyschic. He was pooping outside of the litterbox almost every day. Now he'll occassionally do it but not as often as before.