Heidmann does not directly discuss or mention the Fermi Paradox.
There's no shortage of solutions to the Fermi Paradox
McDonough does a good job covering the familiar pros and cons regarding the Fermi Paradox in these 13 pages, but completely passes over the question of why we haven't received alien signals.
Where Are All The Aliens? What Is Fermi’s Paradox? - …
Explaining the Fermi paradox is a particularly great scientific challenge if ours is a biofelicitous (life friendly) universe, as recent astrobiological evidence suggests it to be (Davies 2004, 2007).
David Icke | The Zoo Hypothesis: Are aliens avoiding Earth?
There must be some way to account for our apparent loneliness in agalaxy that we assume is filled with other clever beings.Solutions to Fermi's Paradox:Thus, the question arises, if it so easy to build Bracewell-Von Neumannprobes, and they has been so much time in the past, where are the aliens orat least evidence of their past explorations (old probes).
The zoo hypothesis (Fermi Paradox)
The apparentfailure of such life to interact with us may be understood in terms ofthe hypothesis that they have set us aside as part of a wilderness areaor zoo.
The Fermi paradox is the apparent contradiction between ..
Like many responses to the Fermi paradox, the zoo hypothesis and its variants make assumptions about the motivations of ETI, and among the first responses to these responses is to question any projection of human motivations onto ETIs. Prior to a survey of the universe entire, with all its life and intelligences (if any), which survey will come (if at all) at a much later stage in the development of our own civilization, the most we can do is to formulate a range of possible ETI motivations (including motivations that do not exist for us, and which must remain unknown unknowns for the time being) and attempt to weight them appropriately in any assessment of the possibility of human/ETI interaction.