Her booker is not doing her any favours - a real shame because Heidi herself is lovely.
Not sure what strategy to suggest - I’ve also travelled a decent distance to see her and nearly got ghosted on arrival. Maybe just allow enough time for the agreed time to be a suggestion, and plan on kicking your heels for 30 mins whilst her booker gets her shit together (literally - Heidi told me one time her booker didn’t answer my texts because she was taking a shit!). Once in, ask Heidi if you can have her direct number.