It’s no worse a threat than getting an airport shuttle or taking a conventional taxi. The latter has been a threat for two hundred years. Are you equally concerned about that?
As for the latter - if he had texted, the text message could have been available to law enforcement. Same thing if he had called using his phone.
Yes, I’m equally concerned about that.
If he used his phone to call an accomplice, why would the police have ever checked it? Wouldn’t they need a warrant for that?