R Markdown cannot find object - r

Question

I want to output Shiny app as a PDF report. But R Markdown gives the following error "Warning: Error in eval: object 'plot2' not found".
The plot works in Shiny, I'm not too familiar with Markdown and I'm getting really frustrated since I feel like I have tried quite a few potential solutions. What am I doing wrong?
Shiny UI
library(ggplot2)
library(tidyr)
library(DBI)
library(RODBCext)
library(shiny)
library(knitr)
library(kableExtra)
ui <- fluidPage(
pageWithSidebar(
headerPanel(""),
sidebarPanel(
textInput("Table", ""),
downloadButton("downloadData", "Download"),
submitButton(text="Submit"),
mainPanel(
tabsetPanel(
tabPanel("Data", tableOutput("tTable"))
),
tabsetPanel(
tabPanel("Graph", plotOutput("plot1")
)
)
)
Shiney Server
server <- function(input, output, session)
{
SQLData <- reactive({
#SQL Query
})
output$tTable <- renderTable(SQLData())
output$plot1 <- renderPlot({
da <- gather(SQLData(), key=Result, 'Control', 'Sample'
)
da2 <- data.frame(da)
ggplot(da2,aes(x=Result,y=Control, color=Result))+geom_point(size = 5) + scale_y_continuous(limits = c(80, 120)) +labs(y="", x = "")})
output$downloadData <- downloadHandler(
filename = "report.pdf",
content = function(file)
{ params <- list(table = SQLData(),
plot2 = {
da <- gather(SQLData(), key=Result, 'Control', 'Sample'
)
da2 <- data.frame(da)
ggplot(da2,aes(x=Result,y=Control, color=Result))+geom_point(size = 5) + scale_y_continuous(limits = c(80, 120)) +labs(y="", x = "")})}
)
rmarkdown::render(input = "Report.Rmd",
output_file = file,
params = params,
envir = new.env(parent = globalenv())
)
}
)
}
shinyApp(ui = ui, server = server)
R Markdown Report
---
title: "Report"
output: pdf_document
header-includes:
- \usepackage{float}
- \usepackage{booktabs}
- \usepackage{makecell}
params:
table: NA
plot2: NA
---
```{r echo = FALSE, eval = TRUE}
kable(params$table, format="latex", booktabs=TRUE) %>%
kable_styling(latex_options="scale_down")
```{r echo = FALSE, eval = TRUE}
library(ggplot2)
print(plot2)