This issue has been fixed in vSAN 6.7U2
Workaround:
This issue only happens when collecting support bundle on vSAN 6.7U1 with WSFC deployed for vSAN iSCSI Target service. Two methods to avoid this issue:
1. Prefer upgrading to 6.7U2 then collecting support bundle.
2. If still in 6.7U1, when trying to collect support bundle on a host, need to put it into Maintenance Mode before collecting, and then move the host out of Maintenance Mode after collecting is done.
How to figure out the iSCSI Target owner host:
From vCenter GUI, find iSCSI host info from "I/O Owner Host" under "Configure" -> "vSAN iSCSI Service" Tab