Was the questioner mistaken in advising his friend not to allow his wife to travel alone to Europe for two years to study, and what can be added to the advice after the friend decided to allow her to do so?

Abandoning prayer and fasting, and openly declaring it, can lead one to the brink of disbelief (kufr). The one who does so must be advised, and the gravity of their action must be explained. A woman's travel for study or other purposes without a mahram (definition) is impermissible. For her travel to the West for study with a mahram to be permissible, the specialization must not be available in Muslim countries, it must be suitable for a woman's nature, and it must not involve anything forbidden. A Muslim must clarify the ruling of Allah and His Messenger (peace be upon him) with gentleness and wisdom. The questioner's anger or failure to act upon the fatwa (definition) does not harm him. Whoever is asked about something they do not know must say, "I do not know," and it is forbidden to speak about Allah without knowledge.