Does the Creed on that bag say it is burnished leather? It looks similar to one that I have that is a similar color and is made of burnished leather. I rehabbed mine (washed/conditioned/Blackrocks) and found the leather wasn't really conducive to rehabbing. I still like mine, but I'm not sure rehabbing it improved it at all.
I'm not one to paint bags or use something like Wood-n-Stuff because acrylic isn't really meant for leather and will clog the pores of the leather. I've re-dyed a bag from a putty color to mahogany. I used Fiebings dye and sealed it with acrylic resolene. It was messy. The resolene also gave it a weird texture. I'd wouldn't dye an entire bag again using that method. I've spot died some brown bags by mixing Feibings dye with conditioner. That worked better. If you could find a similar brown color, you can try mixing a little bit of dye with a thin conditioner like Lexol. My sense is that brown will be hard to match, and that stain may be difficult to camoflauge.
For black bags, Kiwi makes a great black leather dye that is great for spot dying.