Got Ace
Got Asus (C302c) Chromebook w/Playstore capabiltity
Got bluetooth
Got Fitbit app downloaded and running
"Found Ace"
"Connecting .... " and that's as far as it goes.
What's missing? ... Is Fitbit software not coded to work with that environment?
Chrome OS only recently was given the ability for a web based app to interface with a connected Bluetooth device.
I don't know if Chrome will ever receive an update for an android app to communicate with a Bluetooth device. You may want to ask on a chrome support forum.
Fitbit has not written a chrome app yet, and the android app is written specifically for specific hardware that has the android is running.