"succumbed in" is grammatically correct and can be used in written English.
Example: Despite her strong willpower, she eventually succumbed in her never-ending battle against cancer.
Twelve succumbed in the 1960s and nine in the 1970s.
Thurber succumbed in his 60s to comparable demons.
"They succumbed in the cabs of their vehicles".
If young children were still dying at 1960 rates, 25 million would have succumbed in 2007.
Leclerc himself succumbed in November, and the blacks then resumed the offensive under Christophe and Dessalines.
Schächter was himself transferred to Auschwitz in October 1944 and apparently succumbed in a death march.
Trial trees that withstood the disease in his greenhouse later succumbed in the field.
The plants survived waves of corporate downsizing but finally succumbed in 2002.
The closings follow the 140 banks that succumbed in 2009 to mounting loan defaults and the recession.
Most of these succumbed in the early days, and are quartered in Camp Susope, a refugee center.
The Exarchate of Carthage successfully repulsed Arab attacks in the early 7th century, but it succumbed in 697 698.
