cannot mount iSCSI datastore on ESX 7.0u2

Cannot mount iSCSI datastore on ESX 7.0u2:

• after an unexpected reboot, for quite some time iSCSI target was inaccessible (deconfigured on a iSCSI server).
• datastore is easily mountable on neighbor nodes and is currently working/intact.
• esxcli storage vmfs extent list doesn't show it
• esxcfg-volume -l list is empty (already mounted all of the orphan datastores)
• esxcli storage core adapter rescan -A vmhba64 does nothing
• exscfg-swiscsi -s neither
• vSphere Web Client shows no extra devices (all correspond to mounted datastores)
• one of two entities that think LUN is consumed by ESX is the iSCSI target server, which clearly shows that initiator did log onto the target.
• when I remove the target for this missing datastore from static targets list on the ESX, it disappears from the initiators list on the iSCSI target server.
• somewhere deep iside ESX knows about the iSCSI device:

esxcli storage core path list gives

iqn.1998-01.com.vmware:esx2.some.tld:1997342180:64-00023d000001,iqn.2020-02.tld.some.iscsi:node-4-data,t,257-t10.FREEBSD_MYDEVID00310000000000
   UID: iqn.1998-01.com.vmware:esx2.some.tld:1997342180:64-00023d000001,iqn.2020-02.tld.some.iscsi:node-4-data,t,257-t10.FREEBSD_MYDEVID00310000000000
   Runtime Name: vmhba64:C0:T5:L0
   Device: t10.FREEBSD_MYDEVID00310000000000
   Device Display Name: FREEBSD iSCSI Disk (t10.FREEBSD_MYDEVID00310000000000)
   Adapter: vmhba64
   Channel: 0
   Target: 5
   LUN: 0
   Plugin: NMP
   State: active
   Transport: iscsi
   Adapter Identifier: iqn.1998-01.com.vmware:esx2.some.tld:1997342180:64
   Target Identifier: 00023d000001,iqn.2020-02.tld.some.iscsi:node-4-data,t,257
   Adapter Transport Details: iqn.1998-01.com.vmware:esx2.some.tld:1997342180:64
   Target Transport Details: IQN=iqn.2020-02.tld.some.iscsi:node-4-data Alias= Session=00023d000001 PortalTag=257
   Maximum IO Size: 131072

As a workaround I mounted it on a neighboring ESX, currently it's serving VMs, so this clearly means it's okay.

Kinda stuck at this point. Any ideas/comments will be greatly appreciated, you can as well format them as answers.