Mini boss is Anglo and for new toons at that level that have 500-1K HP, he at his 32K can seem very huge. (and risky and deadly

)
As suggested take a friend(s) with you, at least one healer or many healing pots.
But if you decide to do it solo (like I did), then once you make it to the room, you have to engage his supporting army without agroing him and then move close to left side edge. You can get crystal without aggroing him, but I would suggest to use transport skill to get out of there back to Logar.