There isn’t a shortcode that is built into ACF that will work with repeater sub fields. The ACF shortcode is only meant for simple field types.
Generally for more complex fields you must built your own shortcode http://codex.wordpress.org/Shortcode_API
There might be a way to use the ACF shortcode, please note that I have never tried this and it may not work and it is a hack. It also requires knowing the index (row) of the field you want to show.
The meta key for a repeater sub field is constructed
So if you wanted to show the field on the first rows you might be able to use
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