I have a 40 years old vacuum equipment that expirience same temperature range as satellites, from liquid nitrogen to ~300°C. Nothing happened with seals and metals for 40 years. And why it should? Also satellites are not made from cast iron and they do not use bubblegum for seals. There is no rust in space and it is only 1bar pressure difference in the worst case. Many satellites are not even pressurized, so they have no seals at all.
I have a 40 years old vacuum equipment that expirience same temperature range as satellites, from liquid nitrogen to ~300°C. Nothing happened with seals and metals for 40 years. And why it should? Also satellites are not made from cast iron and they do not use bubblegum for seals. There is no rust in space and it is only 1bar pressure difference in the worst case. Many satellites are not even pressurized, so they have no seals at all.