The prototype of TrustedGateway is available on Github: https://github.com/trugw
The corresponding research paper by Schwarz will appear in the 25th International Symposium on Research in Attacks, Intrusions and Defenses (RAID'22) and will be available in the CISPA Publications Database (https://cispa.de/en/research/publications) and the ACM Digital Library (https://dl.acm.org/) soon.