POTUS is good at calling out liers – I bet he calls her out on this, saying she was scheduled on a military flight and HE canceled it
Also remember that POTUS is the Commander-In-Chief of the armed forces, so if it makes more sense for Pelosi to stay and work vs 'visit' with the troops…even a commercial flight into Kabul Int'l wouldn't (necessarily) get her onto a military base … she would need his Authorization to do so.