ArchedThunder
Banned
They were literally TOLD there was another guy and then saw him.
Goku could have teleported then and stopped all the attacks from happening. Instead he decided to stay with Vegeta.
The red dude wouldn't let them "escape", which is precisely when instant transmission comes in handy...
That felt completely artificial and just to give Tien a scene even though Goku should have been able to handle the situation in 2 seconds.
Nobody knew where the shots were coming from, Tien had to track them, so no, Goku couldn't just teleport to him.