Well, I looked it up in the GF 2 script, available on IMSDb.com
In the script, the Klingman-Neri confontaion took place right after Deanna's dopey "What's chintanna ?" question, but before the assasination attempt. It's very possible that given Tahoe's proximity to Las Vegas, Al could have taken off right after the meeting with Ola in Michael's study.