You can recharge the orb by simply using it from the menu. The 5 times event is pretty obvious, you need to get your whole team to die 5 times in battle.
If you already got the red orb, aka the Essence of Rubyro, and you used it to craft something, it should now look like this in your Key Items menu (Key Usables if you're using the Patreon version). Just select it, and press Enter twice to recharge it.
