Chosen Solution
Did not see these items in your teardown of the FitBit Surge. Are they in there and could you tell me who the MFG is?
Looks like a MEMS 3-axis accelerometer, but I can’t find the part number for that or the gyroscope without the device in hand. Maybe https://www.ifixit.com/User/1210134/Tiag…, the author of the teardown, still has the device and would be willing to look?