In Corona times, the number of permitted mourners is limited. Nevertheless, I recommend that you do not postpone the funeral. If they do so, relatives are loading up a pending matter for later and their own mourning process is stalled. Instead of postponing the funeral, I recommend a ritual in a small setting with direct transmission via zoom for a larger group of people, recording via video or the prospect of a subsequent memorial service, for example after six months.
Even in so-called normal times, I put a question mark behind the wish for a silent burial in the closest family circle. Every person has lived his or her story and touched other people with it. The farewell ceremony is a unique opportunity to honour and appreciate this story, which thereby acquires broader (and thus more realistic) contours and sustainable existence. In this story, the bereaved are connected to each other with their very own relationship to the deceased, which in turn can give them support in their own grieving.
The deceased "belongs" not only to his or her immediate family, whoever this may include. In addition to blood relations, he or she has established other ties for which he/she would also like to be remembered. It is healing when all who wish to do so are allowed to say goodbye at the grave and anchor their own memories as well as their own images of hope. Even if the circumstances (tragic or untimely cause of death) mean that words are lacking, it is helpful to name one's own speechlessness and, precisely through this, to overcome it to some extent. This creates a tangible presence and interpersonal closeness.
Once such a common space of resonance has been created, it is no longer disturbing when the coffin or urn is buried by the cemetery gardener after a silent nod. On the contrary, the respectful silence that accompanies this final act of farewell expresses the unique intimacy of the moment, embedded in the great mystery of life that some perhaps call God and others nature.