He waited for Koeman, and then went after the likes of Flick and Nagelsman.
Sure he gave Pep a call, but he himself knew it is a courtesy call.
He himself admitted being fan of a certain German coach.
He knew both Flick and Nagelsman had other deals by May when he went after them (which was too late by the way. He was elected in March, he could try either the next day he assumed office...
Not to mention he didn't hold any talks with Tuchel before the latter signed for Chelsea. He could have waited for the elections if he knew from LAporta himself that he is the chosen one for the bench)
He had serious hopes he could change Pep's mind.
That's why there were no considerations of other coaches before the CL final, no names in the press.
There was an eerie silence that indicated very well what was in Laporta's mind.
If that idea was not there to begin with, not only contacting the Germans earlier could have been done, but trying to struck a deal with Ten Haag before he renewed with Ajax could have been attempted