Femradiel was fully aware that Ryan would notice her absence, and unless she has a decent explanation, he will discover that she went to fight alone against a troublesome foe. Knowing Ryan, he would feel pretty pissed at being left behind, and then he would feel a bit depressed while he looked cute. From her weird perspective like that, she decided to look at a dungeon that would grant her another useful class. At the same time, she headed toward Echidna's base.
Fortunately, her luck was good. She found one dungeon in the Eastern side of Africa that had been recently cleaned. She only found a few hundred Cyclops guarding the place, and once she found the classes there, it made sense that people would often come to clear it.