OK, the way I see it is you have two choices.
1) Do not use the straps at all. In that case you will have to fasten your sides to the concrete. I have NO IDEA what would be adequate for this. It is a lateral load. I have no idea what PSI your concrete is rated at, or what sort of loading the bottom of your pool wall is going to have. The gut feeling I have is that you *might* be able to do it with a bunch of Red Heads and it would work. I myself would not do it based on gut, but I would do the math (or have somebody else do the math)
2) Bite the bullet and rent a gas concrete saw, and cut the necessary channels in your concrete. I would also not backfill the channels with concrete after you put your straps into them. I would use sand. or maybe flowable fill. My concern is the reaction between the alkaline concrete and the metal straps. Flowable fill is basically weak concrete. Embedding the straps is going to lead to corrosion, which leads to failure, which leads to unplanned roaring rapids in your backyard.
Thinking about it, if I had to do this, I would cut the trenches, put my straps together, but before installing them, coat them with a rubberized or asphalt based coating. Place my straps, and then backfill with flowable fill. Flowable fill is a weak, wet, mix. About 1:10 cement to sand with water to make it very flowable. The reason you want to use flowable fill is twofold. One is that it flows, and does not need compaction. Two is that if necessary it can easily be chipped out (if you have to replace the straps)