I wouldn't put the renderText() inside the reactive() function, thats confusing and perhaps your issue.
output$checkedInput <- renderText({
result <- glycoPipe(inFileName)
returnedParam1 <- result$outL
returnedParam2 <- result$numericsL
return(paste("1:", result[[1]], "2:", result[[2]]))
})
I'm not sure what you want to extract each value from the string, but if you have a variable length of list you could perhaps do something like paste(1:length(result),":" ,unlist(result), collapse = ", ")