The Colombia international appeared to be on his way to Turin on Monday in exchange for the Bianconeri's Montenegrin forward and a sum of money believed to be in the region of 1.5 million euro.
Inter then blocked the transfer after an angry reaction from its supporters only to then seemingly resurrect the deal before finally calling it off once and for all Tuesday.
The Nerazzurri subsequently claimed that they did not feel that the "necessary technical and financial conditions were in place" to complete the swap, but Marotta has now reacted angrily to Inter's behavior throughout the whole affair, saying Thohir had disrespected two decent professionals in Vucinic and Guarin.
"This press conference was called after the statement released by Inter, which we found disconcerting," the Bianconeri director told reporters on Wednesday. "We wanted to set the record straight. The Vucinic-Guarin deal was verbally agreed by both parties. [Juventus chairman Andrea] Agnelli received a text from Thohir at 10:48 [on Monday] confirming the deal.
"The main reason we called this press conference was the lack of respect shown toward two serious, professional footballers. My being here is a necessary act to protect Juventus and the professionals who have been treated unfairly."
Marotta also stated that there is no chance of Juve allowing Vucinic to move to the Giuseppe Meazza unless Thohir explains himself to Bianconeri supremo Agnelli.
"As things stand there's no real possibility that Vucinic could join Inter," he said. "Inter asked us for permission to speak to Vucinic back in mid-December - that's when negotiations started. Once it became clear there was to be no money exchanged, we considered the option of a player swap. Vucinic is a great player.
"If there are to be any future negotiations, Thohir will have to offer an explanation to Agnelli - beyond yesterday's statement. But I now know better than to set up a deal with them - not for a lack of reliability, but a lack of seriousness."
- Erick Thohir