You can certainly save the boat. The only question is how much time, money, and material you want to invest. I have seen Royalex boats which had the entire bow stem ripped off, fixed and returned to the water, although they never looked quite the same.
It looks as if the area of damage is larger in extent than what would be covered by the size of what most people think of for a skid plate. I would worry about fixing the cracked area, then put whatever size skid plate you want over the repair.
Is there any visible damage on the canoe interior opposite the external damage? I have seen Royalex boats cracked all the way through the ABS component in which the internal vinyl, which has a bit of elasticity, was still intact and hiding the full extent of the damage.
I would start by removing the external red vinyl layer anywhere it was loose, and for a minimum 2" periphery around any crack. Try peeling it up using a fairly narrow wood chisel, and finish up with sand paper. After doing this, if you find that any of the solid external stratum of ABS is loose from the foam core, trim it away. Any solid ABS which still seems adherent to the foam core, needs to be guttered out with the edges beveled at a 45 degree or greater angle, which will increase the bonding surface of your fabric later.
In the coarse of doing the above, I think it will become apparent to you how badly damaged the foam core is. If it appears to be cracked all the way through and the interior solid ABS stratum is also cracked, I would consider removing the interior vinyl over those areas and guttering the interior solid ABS layer as well.
I repair broken and cracked foam core using G Flex epoxy thickened with colloidal silica powder (cab-o-sil). I know of some who have used Gorilla Glue for that purpose and reported good results. I like G Flex because it can be mixed up and applied in small batches and does not expand unpredicatably like Gorilla Glue. You can also make multiple applications in the same day. You will likely need multiple applications to fill in any damaged foam core as the epoxy settles into the interstices of the core material. Once you get all the cracks filled in with epoxy, or slightly overfilled, you can sand the excess fair and smooth so that your fabric lays down smoothly.
As a general rule, I would use two layers of fabric externally to repair a crack like this, with 6 oz/sq. yd. fiberglass (preferably S 'glass) with the first layer of repair overlapping the intact ABS by 2 inches in all directions, and a second concentric patch 1" or so smaller in dimensions over the first, applying both with unthickened G Flex. Cut the second patch so that its fibers run at a 45 degree bias to those of the first patch, an I would orient both patches so that their fibers are at somewhat of a bias to any longitudinal crack. After the epoxy on the external patches is cured, you can sand and feather the edges of the two patches,
If you find that the interior solid ABS stratum is cracked, I would lay at least one, if not two layers of either 6 oz. fiberglass or 5 oz. Kevlar over that area in the same fashion.
Once you have down a structural repair of the cracked areas, you can decide how big a skid plate you need and apply that over the top.