More context in the article's [source reference](https://www.harboroughmail.co.uk/news/crime/former-leicestershire-police-officer-banned-from-profession-over-crypto-investment-lies-4546493). 
> During the vetting interview, Mr Hussain reiterated he was not close to Person A and they “did not talk”, the hearing report stated. The force later found a series of financial transactions between Mr Hussain and Person A with around £4,000 both received from Person A and sent to him by Mr Hussain. The force said this proved Mr Hussain’s claims they were not close to be “false”.

It seems like they have a problem with "Person A", so the fact that crypto was used in the transactions involved is not really at issue. 

It feels like we're missing part of the story here. Is the issue that he didn't disclose the actual amounts he was trading, or that the person he was trading with was somehow undesirable?