Your primary problem is the voltage levels. The 96Boards Low speed connector is a 1.8V signal level connector (not just the 410c, but all CE compliant boards). you MUST provide level shifting between the Omron sensor, and the 410c board. There is no hope of any I2C communications until you add level shifters.
Fortunately we make it relatively easy to add level shifters. There are several Mezzanine boards available that have level shifters. As an added bonus, they also have the same 4-pin connectors that are on your sensor so all you have to do is plug the sensor in and all of your wiring is complete.
Two example mezzanine boards that will do what you want are: Audio Mezzanine and Sensors Mezzanine
You could also use this one, but the connectors are slightly different LinkSprite Kit
Once you have the correct electrical signal levels correct, i2cdetect should work.
Full Disclosure: I am an employee of Qualcomm Canada, any opinions I may have expressed in this or any other post may not reflect the opinions of my employer.