HAVE:
OP Sample 1: I'll have him killed. [OK, grammatically.]
Sample 2 (control sample by me): I'll have him beaten up. [Ok]
Samples 3: I'll have the house painted. He'll have the work done.
They'll have the boat painted. He had the barn cleaned. She was having
her hair cut. I have the car washed once a week.
Meaning: One person causes someone else do these actions to someone or something.
A person has an action done/performed on someone or something.
Have + object [pronoun or noun] + past participle of verb.
It is a passive construction: "I'll have the boat painted" [by someone]. All the sentences imply an agent.
Compare that to:
MAKE
OP Sample 1: I'll make him be killed. [OK, grammatical, but odd]
Sample 2 (control sample by me): I'll make him be quiet. [OK]
Samples 3 She will make them be polite. We'll make them be sorry.
You'll make them be nice [to other people.]
Meaning: One person forces another person to be into a state or condition through some action that is not given in the sentence.
Make + object (pronoun or noun) + be + state or condition [quiet, sorry, thankful, etc.] This is not a passive construction.
OP sample 3: Why you guys have your phones turned off?
Why you guys made your phones be turned off?
Corrections:
Who has had you guys' phones turned off? [who had the action performed on your phones?]
OR: Why were you made to turn off your phones? [forced to turn them off.]
Who has made you guys turn off your phones? [who has forced you to turn off your phones?]
Please note: to make someone do something is not the same as to make someone be in some condition or state. One is to force someone to do something and the other is to force someone to be in a state or condition: be quiet, be sorry, be killed, be sorry.