Based on the answer i got from the (french) support that i contacted today, looks like the cause may be the problem with acd_cli exposing datas from one client to other ones.
I am sorry that you are having trouble with your Amazon Drive.
I've taken note of your request, but as you mentioned in your email, linux's open source system is not compatible with Amazon Drive. I understand that Rclone is an open source application, which has been validated by ACD, but at Amazon Drive it can not be used for several reasons.
Moreover, we are keen on the confidentiality of our customers' data and do not want them to be susceptible or exposed to piracy.
For my part, I have transferred your request to our developers so that they can study this situation and if possible to set up a possibility allowing some of our clients to go through Open Cell Server validated by Advanced Cell Diagnostics (ACD).