Obi-Wan didn't face the trials. As you've stated, there simply wasn't a gap between the Battle of Naboo and his meeting with Yoda when he could have traveled to Coruscant for testing.
This is confirmed in the official novelisation:
They knew of what the young Padawan had done to save himself from the
Sith Lord in the melting pit after Qui-Gon had been struck down. It
took an act of extraordinary courage and strength of will. Only a Jedi
Knight fully in tune with the Force could have saved himself against
such an adversary. Obi-Wan Kenobi had proved himself beyond everyone’s
expectations that day.
“Ready this time, he was,” Yoda acknowledged grudgingly. “Ready to
train the boy, he may not be.”
“Defeating a Sith Lord in combat is a strong test of his readiness for
anything,” the Council leader pressed. His eyes stayed with Obi-Wan
and Anakin. “There is no doubt. The one who tested him was a Sith.”
This is further confirmed in the (until very recently) canon sourcebook; The Jedi Path: A Manual for Students of the Force where Anakin's own sidenotes state that Obi-Wan didn't have to take formal trials (and why);
There's also a section describing the circumstances under which a Jedi Padawan can bypass the trials, especially if the missions they've been on have resulted in their being tested beyond the limits of the formal trials anyway: