Does eating salty foods make lymphedema worse?

Possibly. A high salt diet can cause water retention and may increase lymphedema but the underlying problem is inadequate movement of the legs to cause the fluid ti pool in the legs.
It might. Excessive salt intake can lead to fluid retention and may make conditions such as lymphedema and venous insufficiency more difficult to control.
Salty food. salty foods may cause fluid retention which is different than lymphedema which is a problem with lymph channels, so when you stop eating the salty foods that swelling will improve.