The Log4Shell vulnerability exploits applications that make use of the Log4J logging component (Alert: Apache Log4j vulnerability (CVE-2021-44228) - NCSC.GOV.UK )
None of our applications make use of the Log4J application. Chimpegration Cloud makes use of another widely used logging component called NLog. According to the developers this vulnerability does not exist in NLog (Is NLog prone to errors like Log4j recently?).
Audit Trail Cloud uses AWS' built in logging system called CloudWatch which is also not related to nor makes use of Log4J.