Yes, you would get a reflection.
We, in fact, can point a radar at the Sun (and as far as I know we've done it, see radar astronomy). However, there's a problem. Although the signal reflects, the Sun is quite far from the Earth so the strength of the signal is very low and indistinguishable from the background noise created by the Sun.
However, if the Sun was as close as the FES claims it to be the signal would be strong enough for us to capture, identify and make use of.