There are a number of complexities in there. Whether the public facility is open to the public or whether it's reserved for certain specific purposes would have a bearing. Assuming, for the sake of this discussion, it's open to the public, there is no implied approval or endorsement by a municipal, provincial or federal government of the ideology or background of whoever is renting the facility, simply because they're using the facility.
If illegal acts are being conducted as a result of that, they must be prosecuted accordingly. However, should you fall short of that and they simply have highly distasteful or objectionable goals, the government should neither endorse nor condemn speech from people who rent those facilities. The government must remain neutral, again assuming that the facility is open to the public and that no criminal incitement is happening as a result of that transaction.