34 Move Silently result (always takes 12), meaning the Solar has to roll a 2 or higher, so yes, most likely, it would hear the Kobold (still modified by distance, though, so then again, might not, considering how far behind the Solar the Kobold is for most of the chase. Kiting is simple enough, given a slight movespeed advantage. It would take time, but stealth usually does. Even if the Solar does hear the Kobold, it is not enough to deny sneak attacks.
And the Kobold isn't moving once he starts attacking, he's hovering, so once again, there is only a -20 penalty, not a -40. Get the facts straight.
He wouldn't initiate the fight after catching up, he'd initiate it after gaining a decent lead (enough to keep the angel within sneak attack range after it moves).
Kobold has Tactile Trapsmith, so if the symbol is set to "look at", he's fine. If it was set to "touch", then it's pretty damn unreliable given it's role/position.
Every tactic I have given has been well within the rules and the Kobold's capability.