BACnet tags are bad, but readRaw works

I've got 2 tags from a Yaskawa HV60U drive that are showing as bad in the tag browser. We have dozens of these drives with all good data showing, so I know the UDT and view are correct. However, I can use the readRawMultiple script and see the value of those tags. Can someone help me understand why the data shows as bad in the tag browser but comes through when I read raw?