I mean, GER can't do that, but it has nothing to do with speed. RF moves around via time travel and dimensional shifting at a higher level than GER does. That's not even a speed contest at that point, it's a hax-off.
GER would actually beat anyone with "just" infinite speed, because GER's "speed" is [(time enemy attacks) - 1]. It just goes "le fuck you" and inserts its own actions before the enemies arbitrarily because acausality is a bitch like that.
Thrawn is like six levels of bullshit past that and I think at this point is a living time stream shaped like a human, so even GER can't do shit.
It's fiction. It doesn't actually have to correspond to reality one to one.
If an author goes "He crossed an infinite distance in a day", then we shrug, give him infinite speed, and then that character wins or ties any contest based on pure speed.
People like the Flash (who outran instant teleportation and achieved a form of omnipresence at one point iirc) are an even higher level of bullshit that specifically does involve more than just physically moving from point A to point B infinitely fast, i.e. a form of time travel or dimensional movement.
Always insert "for the purposes of this hobby" in front of whatever stat a character is given on the OBD. It very rarely corresponds to authorial intent or in-story portrayal, its just the easiest way to quantify someone.