Few people know that the liquid algorithm acts as a mixer, when you enter bitcoins in liquid to make the pegin, these bitcoins stay in a queue to be consolidated in the main addresses of the federation and when you make a pegout you get bitcoins different from the ones you entered.
In this consolidation process all the trace is lost, it is the same system of a mixer or an exchange if you manage to enter the bitcoins in their addresses.
In the future Liquid will have a problem with the authorities and they will force them to change their system.