Sure, give it a try.
The only thing I'd say is put SOMETHING in between the "Hi" and the compliment.
The reason is, you may not have her full attention, and she may still be confused as to why a stranger is talking to her. It's useful to diffuse this by maybe explaining the situation or using a joke.
For example
Hey! I know this is random, but...
Make sure you deliver confidently, slowly, and with a smile
Tell us how it goes!
p.s. Don't worry about what is or isn't a "routine." or a "DHV." It's all just mental masturbation. If it WORKS, it works, that's all that matters
