Thank you for your detailed description. I have researched this specific problem, but I have no practical experience with this exact defect. Therefore, I am unfortunately unable to give a reliable assessment of whether it is absolutely necessary to remove the broken piece or which repair steps would be useful in detail. I would recommend our forum for this, as a wider audience can be addressed there. The following link will take you to the forum:
https://www.digitec.ch/de...
Spare parts - especially individual buttons or switches - are usually offered directly by the manufacturer. Unfortunately, we do not stock these components ourselves and our suppliers do not currently have a corresponding range.
As far as your feedback on Logitech is concerned, topics such as product quality, spare parts policy or customer service are entirely the responsibility of the manufacturer. I would recommend that you discuss these points directly with Logitech.