Section 21 no gas safe cert

Can a landlord serve a section 21 when the tenant does not have gas on and so a new gas safe cert cannot be carried out? Tenant has not paid bill and meter has been capped off and tenant is all round uncooperative with allowing for gas safe to be carried out. Evidence can be shown of multiple attempts, council have written to tenant requesting they allow access to no avail.

An initial valid gas safe was issued to tenant before moving in.

Is there a gas cert from before the tenancy began that you can show was given to the tenant before they moved-in? If so, and you compile evidence of multiple refusals by the tenant, then I would say that its worth a try at court. I have heard that some judges are using discretion to award possession to the landlord in these curcumstances.