[r] assign headers based on existing row in dataframe in R

A new answer that uses dplyr and tidyr:

Extracts the desired column names and converts to a list

library(tidyverse)

col_names <- raw_dta %>% 
  slice(2) %>%
  pivot_longer(
    cols = "X2":"X10", # until last named column
    names_to = "old_names",
    values_to = "new_names") %>% 
  pull(new_names)

Removes the incorrect rows and adds the correct column names

dta <- raw_dta %>% 
  slice(-1, -2) %>% # Removes the rows containing new and original names
  set_names(., nm = col_names)