Could probably make use of the .invalid TLD for this. Should definitely result in less confusion, and it provides something a bit more searchable if people are concerned

    - doubleclick([A-Za-z\-]*)\.net#60u613cl1c4\1.qjz9zk
    + doubleclick([A-Za-z\-]*)\.net#doubleclick\1.g.invalid

https://en.wikipedia.org/wiki/.invalid