So, if I understood correctly, they had a liquidity event where people could cash in their options/shares, and people did. They seemed to expect this expense, IIUC they even took on capital (Series I funding) to make sure they can afford it. The loss is not due to bad financial performance at all (the article mentions increased sales by 30%). Hats off to Stripe for making sure that their employees, who had to sit on their options, had a chance to finally cash in on the success of the company.
(If my understanding is correct, the title is quite misleading, because it makes it sound like Stripe was struggling. When in fact they flexed their muscle by taking on cash to hand to their employees).