This is gonna sound really dumb and has probably already been answered,but what other ways are there to survive the Scratching of a session?

Not being in the Session/Universe and Dying to get to the Bubbles are the two ways shown in canon, and really, the easiest ones. I could think of other ways however, perhaps certain Void Players could void themselves and the group out of existence for a moment and blink back in after the Scratch has happened. Alternatively, a powerful Time and Space Player together may be able to create a pocket in the Session that isn’t affected by the powerful Time-Space energies released by the Scratch and erasing everything around them.

Otherwise, though, you really are just better off finding out a way to exit the Session.