what if falcon heavy had an engine failure?

if an engine on one of the side boosters of a falcon heavy was shut down prematurely, could the payload be placed in it's intended orbit?
we have already seen that when a merlin engine on a falcon 9 rocket is shut down, the other engines must burn longer to make up for the lost thrust.
if one of the engines on a falcon heavy side booster was shut down early,

would that booster stay attached to the core stage longer?

would that booster be dropped at the same staging point as the other booster with excess fuel still aboard?

could the crossfeed system pump out the excess fuel before staging?

could the merlin engines be over-throttled to make up for lost thrust?

or would the other booster be throttled down, making both stay attached longer and burn longer?

anyone have a guess as to how this eventuality could best be handled?

The only people who can answer most of those questions are SpaceX.... anything else would be guesswork.

I agree with JamesHughes. However, since SpaceX has stated, that crossfeed would be an optional feature, and because an asymetric thrust vector would pose all kind of problems for attitude control, I would assume, that the other booster would be throttled down and both would burn longer until depletion.