Looking at the tips and notes it seems like it should be "Jij zal jouw vriend gebeld hebben".
How do we know what order the verbs go in when they get pushed to the end?
Jij zal jouw vriend gebeld hebben. should be a good translation. When you lost a heart you can report it ---gebeld hebben and hebben gebeld are both good ( at the end of the sentence )
When any sentence like that could be use, should not in every future perfect sentence be precise time of event taking place or sequence of descriped events added?
"Jij zou jou vriend hebben gebeld" is also correct. Zou en Zal is interchangeable in this sentence.