I'm writing a story set in a version of the modern world, but with a hidden magic user society. Mages all come from one of seven "Houses", each with particular expertise in one kind of magic. The Sixth House, House Lyril, is the mages skilled in manipulating minds, and the current leader is Lady Lyric Lyrilie (which means Lyrildaughter or Lyrilchild in their language), who seems to be secretly working against the magical governing body she sits on, the Coven, and enthralling/charming other mages and even mortals to obey her.
In this world, there are two types of mind control, direct and indirect. Very few non-Lyril mages can protect their minds from either kind, but most Lyril can protect from both. However, it is nigh impossible to discover Lyril magic in a mind if the magic isn't active (so good Lyril make good therapists, but bad ones are terrifying). Importantly, any time the thrall is acting on an order or similar, actively or passively, their eyes glow one of the 2 colors of the controller's magic, which can be used to identify the controller (each mage has two unique, "pure" colors of magic that mix based on emotional state; mind control magic almost always manifests as the positive magic color).
Direct control is called thralling, and it requires active magic from the controller. When enthralled, the thrall's actions can be directly controlled and influenced, subtly or not, and they cannot disobey. The controller can verbally give commands and directives that are retained after direct control is gone, along with granting pleasure or pain to the thrall. Generally, thralls call the controller Mistress or Master So-and-So, and are very subservient.
Indirect control is called charming, and it is passive but requires previous thralling. It mostly just stops them from disobeying, makes them think only positively about the controller, makes them follow orders given under active thrall, and if asked about something related to an order, they have a moment of head pain and then forget the question and the last few seconds. However, mostly the thrall seems normal.
How could a mage, knowing this information, positively identify a current instance of charm/indirect mind control when they haven't seen the direct enthralling happen? Good answers will be relatively specific to the magic system (so not simply "they should just not have any friends") and easy to put into place in the modern world with minimal cost (so not "pay people to watch your friends all hours of the day).