Go to the auto parts store. What you want is black silicone sealer.
Use that to glue down the pieces that are pulled up.
Small tiny nicks--you can dab some of the sealer into the nick. The black sealer should blend well, but it will be shiny, so use your slightly dirty finger as it starts to dry to give the new glue a matte finish. You can use your fingernail or a flat-blade screwdriver to create the mottled appearance and the valleys of the Tolex.
Now you have some areas left that are missing the Tolex. Remove the back panel. There will be areas where the Tolex is folded over the edge. You can use a sharp knife to cut out small bits of this unseen Tolex, cut it to the right shapes, and glue it down with the black silicone sealer. Use small dabs of the sealer to blend the seams.
Work slowly, and be patient.
I've done this to a couple of beat up cabs, including one of my Mesa 412 Half-Back cabs that the previous owner had taken on many tours. Using this technique, and a bit of Krylon to repaint the metal grill--well, it doesn't look like new--but it will certainly pass the "3-foot rule". And on a darkened stage, it looks really good.
That's a nice amp, and it would be worth the little bit of time and effort to make it look as good as possible.
And invest in a Tuki or D2F cover to keep it looking nice.
Good Luck!
Bill