Yeah it's a bit of a double standard really. There was usually police around outside fabric so aren't they just as much to blame as the people searching on the doors?
The doormen and club have a degree of responsibility for what goes on on inside the club (including trying to prevent drug dealing), the Police are not there purely for the club.
In the same sort of way that it's the Clubs responsibility to make sure it's staff know the law about serving alcohol in regards to age and how drunk the buyer is.
If club staff were dealing then that would be a very big issue for the people deciding on the club's licences, especially if the management were seen to not have taken reasonable steps to keep an eye on what their staff were doing (in the same way that both the person who sells alcohol to underage people, and the employer can be held accountable and if it happens repeatedly the licencee will lose their licence). Employers tend to be expected to know what their staff are doing within reasonable limits, such as whilst on the job, and take steps to make sure the staff know what is allowable, what the law is, and preferably document it so they can show they've taken those steps.
What about the 108 people who died in police custody over the same period that the club was open? Shall we ignore that instead?
If that's the usual way that that stat is used it's incredibly misleading, as from memory it's actually "death after contact" rather than whilst in police custody/the cells/back of the van, so someone could drop dead of a heart attack whilst talking to the police and it would be counted, or someone could die of a drug overdose whilst the police are giving them first aid and waiting for an ambulance, or could commit suicide the day after they've left police custody (IIRC it includes deaths within a set period after police contact).
There have been cases where members of the public have restrained someone whilst they waited for the police and when the restrained person died it was counted as death in police custody, despite the police recognising that the person was not breathing upon their arrival and immediately giving first aid.
It's also worth noting that every "death in custody" is investigated, usually by a third party.