one simple way is to declare are the top of your script a lookup for the new names that need map to old/expected names.
library(dplyr)
name_lkup <- c("old1"="new1",
"old2"="new2")
(new_df <- data.frame(new1=123,
new2="xyz"))
(old_df <- rename(new_df,
all_of(name_lkup)))
#then run process on old_df