Apart from a requirement to wear masks on the site (and for anyone on common property) all the restrictions on building workers that existed before seem to have been swept away.
You could ask the site supervisor to make sure the workers observe social distancing. And you could limit the number of people travelling in the lift at any one time.
Interestingly, I wonder if the reasonable restrictions I suggested in my previous reply still apply, now that your OC has rejected the first application.
I would get on to that immediately and just forget about any Covid-19 rules – they don’t exist, and that means anyone, vaccinated or not, can be allowed on the site.