Figuring out how to mend a tank top

You may remember this awesomely damaged camisole from my post about Lilo, the Amazing Wool-Eating Cat.

Draped over the shoulder is a folded sleeve I cut off from another shirt during this project. I bleached the fabric by setting it in a solution of 1 cup hydrogen peroxide, 1 cup water, 1 tablespoon washing soda, and a dash of detergent overnight until it reached a shade that complemented the camisole’s. That’s what I’d like to use to make the repair, possibly after doing another round of lightening.

Both fabrics are merino wool of similar knit and weight.

Bonus points if the repair is attractive enough for the camisole to be worn as a top layer. Right now, I’m thinking along these lines:

The vertical seam would go where the remnants of the side seam currently lay (Lilo fortunately didn’t eat across the seam) and there would be decorative topstitching along both sides of the diagonal seam. (Fortunately I’m better at sewing than drawing with a steady hand.) Still not sure it would be presentable in public, though.

Anyone have a better idea? I also have the fabric from the other sleeve from this project, but the usable space is not as large since there are runs in the fabric.