I would say that nail is crying out for a fibreglass or silk wrap to be honest.
Regardless of what system you usually use, a wrap will help bond where its broken and will look and feel most like the natural nail, as oppsed to an overlay. The fibreglass will add the strength needed to help the break grow out, whereas certainly gel probably wouldn't be as strong, and I feel you would find the gel breaking again before it has grown out.
You can then treat the nail as normal and do not have to overlay the rest to match, or can add your chosen overlay on top in the future if you want to.
if you aren't trained in fibreglass, maybe another geek closeby would help. I also attached a tutorial by our fab fibreglass guru, Ruth, to give you more of an idea, abeit this is for a broken corner..
http://www.salongeek.com/nail-finis...ow-replace-broken-corner-nail-fibreglass.html