That lens is in Compur #00. Most #00s have no T setting and none has a blade arrestor ("press focus").

The 58/5.6 Grandagon's #00 has no T setting. You're not missing anything, your best option is to use B and a locking cable release.

The 58/5.6 Grandagon's #00 has no cable release socket; not a problem when it is used on an XL 'cos the XL barrel for it has a cable release socket. But this makes the lens in the original shutter pretty unusable on other cameras. I had mine reshuttered in a #00 with cable release socket, use it on 2x3 Graphics and Cambo.