If I twinned spell cast Glyph of Warding as a spell glyph, can I store two different spells, or does it need to be the same one?

I have a sorcerer wizard. He wants to use twinned spell metamagic to cast glyph of warding as a spell glygh, twice on two different surfaces.

Spell Glyph. You can store a prepared spell of 3rd level or lower in the glyph by casting it as part of creating the glyph.

Can he cast two different spells to be stored in the spell glyph, or would it be the same spell twice?