Lost cause disk?

Hi,

This is probably a lost cause disk issue but I may be lucky and someone in this forum might tell me otherwise

RX7620 has two internal disks on vg00. Root disk is fine, the disk with /opt is not fine

ioscan reports all ok c0t6d0 c3t6d0  both CLAIMED, c3t6 has the problem though as reported by lvm

LVM : Failure in attaching PV (64000/0xfa00/0x2) to the root volume group.

reconnect -r says not ok

Scsi(Pun6,Lun0) HP 146 GST3146707LC     HPC1 (160 MBytes/sec)                 
Scsi(Pun2,Lun0) _NEC    DVD_RW ND-3550A 1.31                                  
Scsi(Pun6,Lun0) HP 146 GST3146707LC     HPC1ERROR:    Cannot determine device capacity
Scsi(Pun6,Lun0) HP 146 GST3146707LC     HPC1  

diskinfo /dev/dsk/c3t6d0 shows device busy ( presumably as it's part of the VG and lvm is retrying)

At the EFI level I think I am only seeing one disk

Shell>  devtree
Device Tree

    Ctrl[7F] LSI Logic Ultra160 SCSI Controller
      Ctrl[81] HP 146 GST3146707LC     HPC1
        Ctrl[82] FAT File System [FAT32] 499 MB
        Ctrl[83] Acpi(HWP0002,100)/Pci(3|0)/Scsi(Pun6,Lun0)/HD(Part2,SigA4A58C02-0812-11DE-8000-D6217B60E588)
        Ctrl[84] FAT File System [FAT32] 400 MB
    Ctrl[80] LSI Logic Ultra160 SCSI Controller
      Ctrl[85] _NEC    DVD_RW ND-3550A 1.31
  Ctrl[09] Acpi(HWP0002,11C)
    Ctrl[86] Acpi(HWP0002,11C)/Pci(1|0)
    Ctrl[87] LSI Logic Ultra160 SCSI Controller
    Ctrl[88] LSI Logic Ultra160 SCSI Controller
<truncated>
 

I've tried reseating but getting to the end of things to try. In case it's just the disk label that's missing is there a way to get this back?

Thanks

Paul