Concrete is dry in 24-48 hours. Sand and wooden poles could be enough.
Some ideas on the how, could be found in this video, on how they created a bridge in the middle ages: https://youtu.be/nJgD6gyi0Wk
I'm pretty sure engineers could find better/faster solutions than what I'm proposing.
This means you need to provide .. lets see, a trapezoidal cross section is 500 square metres.. 100,000 cubic metres of filler. Twice. And then you probably need to curve it to resist the pressure, so that's a bit of a lowball figure. You can't dam any less, because the ship is stuck sideways across the canal.
Using some old numbers for concrete pours in Ireland (2016 era) per cubic metre, that's 7.5 million Euro worth of concrete. Sure, you're not going to use pure concrete like that though - you'd probably start dropping massive boulders in first, and then try to cap/fill it.
Have a read of https://en.wikipedia.org/wiki/Palm_Islands to get a feel for how long it takes to lay in that much material..
And then you have to dig it all back up to reopen the canal.
A sister comment mentioned 400$ million per hour worth of trades being blocked by this, so the cost of this would probably recouped by the time the order is cleared.
but it's not $400M lost? If you ordered a $100 package from amazon and it got stuck in transit it's not a $100 loss.
They need some construction which they can add water faster than it escapes the container, to raise the water level.
If stacked water based cofferdams would be a solution ( idk depending on these requirements, current, ..), it could be done quickly if they have the bags ( multiple teams, multiple locations to start and filling the coffers with water as soon as possible). The budget to fix this fast is probably pretty high. A lot would depend on how much they need to raise the water for the pressure, so it wouldn't collapse. ( Fyi, i do think water based coffers would collapse, but perhaps sand ones can be placed in top on it for 1 meter).
Palm islands needed a construction that holds multiple years and isn't the same as the issue in the Suez canal.
Tu be honest, I'm just thinkering about the variables that could make this work, instead of dismissing it immediately.