Yeah, I couldn't get Magdalena to appear, even after I offered the 10k. I waited too long. I tried to complete the quest after Arvendale. It
must be done before the Arvendale mission (I read that on the Laxius Force site)
. The second time around my team was Random, Sarah, Luci, and Wendy. I used the beauty potions on all four and offer her 20k, and she finally appeared. Maybe you can get by with less gold, but I remembered someone saying they offered 17k and nothing happened. I wanted to be on the safe side. I had to take on Arvendale for a second time because I missed my chance to complete it the first time. It appears to be a very important quest.