HRM Dual and Garmin Connect App

I am soon going to start doing kettle bell workouts, which means I won't be able to wear my Garmin 45 watch (at least the normal way) without it getting damaged by the kettle bells. I know that the HRM-Dual or any chest strap is not supported by the Garmin Connect app, so I won't be able to upload my workout to it.

My questions are...

If I get the HRM-Dual and connect it to my watch, and wear my watch backwards or put it in my pocket while wearing the HRM-Dual, will it upload the data to my watch? And from there I can download the data from my watch to the Garmin Connect App?

I'm not worried about it logging anything else but my HR. I just want to get some sort of data into the Garmin Connect App. I never owned an HR strap before, so I am not sure how it works.