>>13285920E = mc^2 brotato. Einstein's famous equation. Plug it in.
https://en.wikipedia.org/wiki/101955_Bennu^ double its length while keeping roughly the same mass and you'd probably get Omuamua approximately (since we don't know its actual mass, we have to approximate).
So:
E = (7.329±0.009)×10^10kg * (290,000km/s)^2
E = 6,586,976,704,962,136,483,560 MegaJoules
>While your average supernova generates roughly 10^44 joules of energy>dropping the exponent by 9 gets you a MJ energy conversion>so 10^35 megajoules of energy>how fucked are we>6,586,976,704,962,136,483,560MJ>6.586 x 10^21 MJ of energy> 21 / 35 = 0.60Omuamua going 90% the speed of light smashing into the Earth will release 60% of the energy of a supernova detonation, which can outshine the collective energy of an entire galaxy. We're SO FUCKED, the solar system will cease to exist. The Sun will be launched in the opposite direction, and may potentially destabilize from the blast itself, itself collapsing into a nova and leaving behind a white dwarf on its place accelerating inwards towards the galactic core or outwards towards Galactic North.
