Hi @xScottHein
here is what I think it is.
Is this Checkmk Installation a bit older or was it upgraded from RAW to CEE or something similar?
That could be the reason that some host show that icon because in the RAW edition there is no smart ping feature and the host check is done by check_icmp. After the upgrade to a enterprise edition the default host check is done via the smart ping. unfortunately the smart ping won’t give you rtt or packetloss graphs and thus no performance data. But the Checkmk installation still has the old RRD Data for the hosts and that’s the reason the icons are shown.
The easy work around would be to change the host check command for all hosts to check_icmp and not smart ping but remember it could have an impact on the performance of your installation.
I know it’s an older post but maybe you still face that problem 
Regards
Norm