A 35 pass Gutmann wipe will take very long time and i don't think that this is a good solution for a usbdrive.
Try gparted to see if there is any unsual partition table that don't belong there.
If you can't find any unusual partitioning try to open the usbdrive with an hex-editor that is able to open drives such as winhex.
Overwrite the entire drive with zeros after that make a fat format with Gparted.
Note that 35 pass Gutmann and editing with a hex-editor can harm the drive even more !
If you have any warranty on that drive go for a replace or repair (mostly such devices can't be repaired so it's a replacement).
PS2 SCPH-70004 V12 PAL + HDCOMBO + 160 GB Samsung HDD + OPL 0.9.1
PS2 SCPH-70004a V13 PAL Satin Silver
2 x Official Sony 8mb card +FMCB 1.8c + uLE 4.42b
Datel Max Memory 32mb card +FMCB 1.8b + uLE 4.42
Memor32 + Memento FW 1.2e