Curate, connect, and discover
I doubt that Trent will mess with Yussa for a number of reasons;
1) The murder would not be easy to hide (many bystanders that watched the chase and would his death change the outward structure of the tower?).
2) Killing a powerful figure in of an allied nation is not excusable even if said figure has a complicated relationship with local politics.
3) Killing Yussa, the Archmage that mentored Oremid Hass (a fellow Cerberus Assembly leader) would provide more evidence to prosecute Trent from both internal and external investigations.
4) Yussa is member of the Arcana Pansophical, which just in general would be stupid of Trent to mess with (not even including the attention it would draw from Allura and her Whitestone allies).
5) And Trent is the Archmage of Civil Influence, so his job title and importance is only supported by the public image of peaceful civility Trent must maintain for the Assembly. He’s very unlikely to jeopardize his own public influence and governmental power for a mercenary chase.
Is no one else concerned about the fact that they left Yussa defenseless and in a trance alone with Trent and his assassins???? Who may take the opportunity to take out a potential enemy and blame it on the people who are already being blamed for Vess's death???