A careful drone flyby when the mother was away feeding shows two intact eggs in the middle of the nest. There may be more to come as four or five are a typical clutch for a greylag goose.
Update 21 May 2023. The two goose eggs disappeared a few days later, then two more appeared but the female crushed one. The remaining one survived and just two hours ago hatched and the gosling is already happily swimming around the pond!