Just bring in a Bagger 288[1] and use it to excavate a new diversion canal in front of the ship long enough to get it out of the main canal, bada-bing bada-boom. Simple!

[1]Obligatory: https://www.youtube.com/watch?v=azEvfD4C6ow

That beast is really outstanding and would probably be able to do the job in reasonable time. This machine is so insanely large, it would fit into any sci-fi movie. The craziest thing is, some years back it was driven over a distance of 22 kilometers cross country to a different site, which was just mindblowing.

Put balloons around it to give extra buoyancy. That should work.

That actually is something that you can do in smaller salvage operations. The technical word for these balloons is lift bag.

I searched for the biggest ones I could find this week and it was something like several tons. So we only need about 10 thousand of them.

And the key words are "smaller salvage operations".

Or with crabs, potc style! /s

Why don't they just give me a long enough lever so I can simply lift the ship out of the canal?

Put huge hydraulic cylinders below the ship. The obvious problem is, what are those cylinders anchored to?