The solution was very simple and sleek - instead of populating user from HTTP Context object (which was unavailable in this part of code), I populated user from implicit request and then passed variable to my custom template:
def getPasswordChangePage[A](implicit request: SecuredRequest[A], form: Form[ChangeInfo]): Html = {
val userName = request.user
views.html.secure.Registration.passwordChange(request, userName, form)
}
The code above is part of MyViews.scala code.