Does that error message mean the person is ignoring your text?

I am looking for my son - I have not been able to reach him in almost a month. I found out this morning that he was fired from his job and told them that he was 'going out of town' before he picked up his last paycheck.
He's 22 years old --- and lives 8 hours away from me. Over the last couple of years he's moved around a lot (but always within the same city).... so I find myself at this moment not even knowing where he is living.

Anyhow - I have come to a place where I'm near panic - after a month of trying to reach him and not getting him, I finally called his work this morning (his only cell phone was a company cell phone) - and that's when I found out that they fired him.

So, my ex husband lives there too and sometimes my son goes to see the man.... so I tried to call my ex (it's been 5 years since I've done that, LOL) anyhow, he didn't answer, so I sent him a text asking him to please call me ....

In a minute or so I got a message back from Verizon saying that they tried to deliver the message 3 times but it was not answered.

I'm wondering if that message means that the man is hitting 'ignore' on his phone - or somehow refusing receipt of the message and that's why I'm getting that error.
Anybody have any clues or ideas .... this just is not the time for dumbass to be playing games (which he's most popular for doing as a rule).