In the original article by BBC, which Vesti is referring to, the medical staff does not state that they didn't diagnose the Skripals. They do explain though, that when the Skripals were found, an opioid overdose was suspected. "We were just told that there were two patients down in the emergency department who were critically unwell and they would be coming up to the unit," recalled ward sister Ms Clark. But when police became aware of Mr Skripal's former career as a Russian spy, they told the hospital and discussed the possibility that he may have been the victim of a targeted attack. www.bbc.com/news/uk-44278609,

Further debunking by the Insider.

Many competing and contradictory stories promulgated by Russian state-controlled media on the Skripal poisoning https://euvsdisinfo.eu/disinformation-cases/?text=sergei+skripal&disinfo_issue=&date=

On Sunday 4 March Sergei and Yulia Skripal were poisoned in Salisbury with a military-grade nerve agent of a type developed by Russia. As for the scar on her throat, news outlets, including the BBC and Telegraph, have described it as a result of a tracheotomy, a surgical procedure which opens a hole in a person's windpipe to help them breathe. She did has not shared specifics of her treatment, but described it as "invasive, painful, and depressing." http://uk.businessinsider.com/skripal-poisoning-yulia-skripal-neck-scar-hints-at-painful-recovery-2018-5?r=US&IR=T

For the UK response see: https://www.gov.uk/government/news/novichok-nerve-agent-use-in-salisbury-uk-government-response

The OPCW have confirmed the UK findings in the case. "The results of the analysis by the OPCW designated laboratories of environmental and biomedical samples collected by the OPCW team confirm the findings of the United Kingdom relating to the identity of the toxic chemical that was used in Salisbury and severely injured three people." https://www.opcw.org/news/article/opcw-issues-report-on-technical-assistance-requested-by-the-united-kingdom/