You can easily put the a,b,c values in the title of the coord file via:

Open write card unit 17 name @9xtl_alamin1.crd
Write coor card unit 17
* Optimised coordinates for crystalline alanine. The lattice is
* optimised with a = ?XTLA , b = ?XTLB and c = ?XTLC .

However, it is also fairly straightforward to go one step further and create a stream file for the crystal setup using the optimized values:

open unit 11 write card name opt-cryst.str
echu 11
echo * crystal setup
echo *
echo Crystal Define Orthorhombic ?XTLA ?XTLB ?XTLC 90.0 90.0 90.0
echo Open read card unit 14 name @9xtl_ala.xtl
echo Crystal Read card unit 14
echo Close unit 14
echo return

In subsequent scripts, the crystal setup is accomplished via:

stream opt-cryst.str