Comment by jkrah for You can temporarily disable compute services on the controller with openstack compute service set.I suspect, however, that some misconfiguration prevents the compute nodes from receiving instances.

Sorry to ask the obvious, but you have 'sourced' overcloudrc and not trying to depoy using the 'stackrc' (undercloud) credentials ? Other things to check.. (again using . ~/overcloudrc) * openstack hypervisor list * check you hypervisor resources again the flavours