Ok so I managed, like a genius, to break off a bolt inside the valve cover while re-assmebling the recirculating cover after redoing the gasket. It is on the passenger side, the small bolt closest to the front of the car (on the right).

The bolt broke off pretty well level with the top of the "tower" that it threads into.

Is it possible to just fill that hole with all kinds of RTV sealant once the recirc cover is back on, or is the bolt absolutely necessary?

Thanks!