My First Scam Call

Yesterday I got my first ever Scam call. The phone woke me up at 7AM. I ran to the phone and picked it up just as the "leave a message" recording kicked in.
"Hello"
"Hello. You know who this is, right?"
"No."
"It's your grandson."
"Stephen?"
"Yeah."
This didn't exactly sound like Stephen so I commented to which he said he had a bit of a cold.
...
"Grandma, I'm on a trip. Did you hear about it?"
"No."
"Well, I'm in  Mexico."
"On a mission trip?"
"What? You're cutting out. Are you still there?
"Yes."
"Grandma, (He kept calling me Grandma. Stephen doesn't call me Grandma.) What did you say about a trip?"
"Are you on a mission trip? What kind of trip are you on?"
I'm on a vacation with my friend, Michael."
Here I started to laugh.
"We're just down here visiting to see the ruins. You know about the ruins, right?"
"Of course."
Stephen isn't this forward. There is no school vacation that I know of. Stephen wouldn't have gone to Mexico without his parents, and most likely wouldn't have called me from there. Besides he's coming to see me in a week and a half.
"Michael's dad works for American Airlines and he gives Michael free trips once a year. That's the  only reason I would have came down here."
Whoops! Stephen doesn't make grammatical errors in his speech like that. Who is this?
"Stephen, when are you coming to see me?"
"Well the trip ends Sunday so we should be back Sunday night or Monday. When are you available?"
"Any time."
"OK I'll probably see you then. Grandma, I have something to talk to you about. Do you have a minute?"
"Yes."
"It's very important so you have to keep it a secret. I want to tell everyone face to face, so you have to promise to keep it a secret."
"OK."
"You promise?"
"Of course."
"I  got arrested this morning."
Silence.
"For what?"
"During our layover we were hungry so we stopped to get a bite to eat and some souvenirs."
At that point, my recorder went off with a beep.
"Everything went bad from that point on. What was that sound?"
"Oh that was just my recorder going off."
I think that spooked him but he kept going.
When he finally paused, I said, "Stephen, what is your last name?"
(Sounded like) "Eye width. Why?"
"Because you're not my grandson."
Click.

It pays to know your grandson!
Insightfully yours,
Paulita