Not adding up, north of Odstone

While we await further information from Watermead Park, we have a conundrum north of Odstone (within the Bermuda triangle of black lab sightings). We mentioned that while we were in Mexico there was a mystery black lab, loose, seen by 2 women who know the area well and couldn't place it.
Last week we had a call from a lovely man called Simon who said he had been out on his horse all morning (does the route regularly) and had seen a black dog for a couple of hours, sitting contentedly in a field where some tyres have been dumped. This is a field which used to have maize at the height of the Bermuda triangle times so I knew it well, near a humpbacked bridge going over a disused railway with lots of nice hidey holes.
Tim and I were in work so I rang dear Tori on spec, and she leapt into action (it's 10 mins from home) with dog biscuits and the full "how to get a timid dog to come to you" training. Simon had said he thought there was a mark on the back and grey around the muzzle. I was besides myself with this information, and at the right moment Tim, whose diary said he was examining medical students' finals all day, appeared by my side saying they were overbooked with examiners and he had a free day totally unexpectedly. Within 5 mins I'd despatched him!
He arrived to find Tori who'd coaxed the dog to her, discovered it was a collie cross and not Sky, rang Ann our lovely dog warden and by the time Tim got there it was all over, with the dog en route to Animal Rescue in Hathern.
It turns out the dog was about 10 months old, didn't look like it had been "lost" for very long and remains unclaimed today, a week later.
Simon was so apologetic and there seemed to be no reassuring him that, but for people like him who make such an effort to contact us, we'll never find our little boy!
So is this the dog seen 2 weeks earlier? It doesn't sound likely but we don't know. We'll keep an open mind and remain fairly reassured that our spies are out there.
Meanwhile another doggy website has taken us on after a pleading email from me and will publicise a flyer about Sky amongst many of their connections. Thanks to Val from Barlestone who passed on their contact details.
Sad news a week ago. A neighbourhood dog attacked our hens 2 days in a row and on the 2nd day (literally we only let them out for half and hour and were with them but for 5 mins when Tim went to his tool-shed and I unloaded some washing) the dog killed beautiful Bossy (pack leader). Scraggy and Honey have been injured but are recuperating (with the aid of nice vet Linda). All are confined to barracks while we sort out additional protection (electric plus post-and-rail fencing). Poor Bossy had a slow death which had to be terminated by Tim in the end as we couldn't bear it.
And to think of all the time Tim has spent peeing around the hen run, with us thinking foxes were the main enemy (seriously, it's definitely true that this human scent keeps them away - loads of people say so................... ask anyone who keeps hens - OK, too much information LOL!)