Using a hands free device is only legal in so far as it's not a fixed penalty offence. Not being in proper control of one's vehicle as a result is the point where it becomes illegal - but this aspect is less troubling than him driving blind.
I've found an earlier report which describes the location and home address at
https://www.cambstimes.co.uk/news/woman-from-chatteris-dies-in-crash-1-5807428 and combined this with the OP report to figure out the likely route was
https://cycle.travel/map/journey/139086 (with 1 marking the collision location) and you can see that the driver has probably been travelling in the same direction for about half a mile before the collision. So driving blind does not seem like a momentary error so I don't understand why the lesser offence was used.
Now, to correct what I wrote to
@icowden earlier, this is not where I suspected. It's actually the only stretch of A141 north of Huntingdon that has a cycle track, which was built along with the former "ghost Tesco" now the "Jack's" and "Poundstretcher" bucket shops. However, because the roundabout has no cycleway across its islands, a southbound cyclist would pretty much have to bravely stick their arm out and turn right at the roundabout, then make a U-turn left onto the cycle track across the superstore roundabout exit at
https://showmystreet.com/#v8ea1_wl2_7d.d_-7h43 - and then 700m later, after a dip to an underpass that would take southbound riders on a long detour and climb back up, crossing a side road without priority, you'd have to cross the A141 without priority or refuge at
https://showmystreet.com/#v89ym_v3u_5m.s_-3g43 - so I can understand why southbound riders might decide it's better to turn left, ride 700m of A road and turn left off it, rather than turn right, U-turn left, cross a side road and cross both lanes of the A road. So, the council should still be flamed — but for building half-useless disconnected shoot rather than not building anything!