Hi Iza,
if the call-back may happen in an different passage, then this could be a step towards solution:
Passage Start:
Protagonist makes a phone call and says
"<<link "Hey">><<set $call to "w1">><</link>>" or "<<link "Hi">><<set $call to "w2">><</link>>" or "<<link "Sup">><<set $call to "w3">><</link>>"
... some other text ...
[[NextPassage]]
Passage NextPassage:
Later that day, a call came in. Protagonist took the phone:
"Hello?".
From the other side, Protagonist hears:
<<switch $call>>
<<case "w1">>
"Hello, my friend, you don't know me, but listen carefully ...."
<<case "w2">>
"Darling, you won't forget to buy the meat for this evening, will you?"
<<case "w3">>
"Police departement calling. Inspector Henderson here. Did you receive an unusual phone call this afternoon?"
<</switch>>
... How will the story go on ...
This is my first try with sugarcube, so this solution might be the worse, but anyway, it looks like it is working. I would expect that one could <<include>> whole passages instead of writing 'case' the sentences down right there.
If you meant to display the different text variants to display on the same passage - immediately after choosing what to say - then there must be found a binding between "show/display text" and the triggering link.