Sondland testified that it was indeed Trump.
I think Sondland likes to impress people with the fact that he can get to POTUS.
No one's disputing that the call took place or the basics of what was discussed.
The only potential disagreement is Sondland remembered discussing "Burisma" and Holmes said he heard "Biden".
Still, just how in the world do you OVERHEAR a conversation with POTUS? That doesn’t add up.