She would have been better off just saying nothing in a way.
But then I guess they had to come up with something as to why Tim was A. looking so well and B. not actually dead!
Sally Walker must have thought this miracle improvement nonsense would explain why he wasn't nearing end of life and was instead just as healthy as he'd been years earlier.
The person that approached Chloe may well have seen him working on the farm, and never saw him on an off day, ever.
So, if it's the case, someone that knew them was suspicious because he never had a 'bad CBD day' over a number of years, then it's likely there's either nothing wrong with him, or if he does have something it's relative minor compared to CBD.