As far as I know, CRAN doesn't rebuild vignette, it just use the html/pdf you build locally. So are you sure when you build your package, it contains the vignette you want? You can check it here: http://r-pkgs.had.co.nz/vignettes.html#vignette-cran
Edit:
For the vignette to pass the R CMD check
, this is my method:
Firstly, do this for your Rmd file, this will generate the md file for the vignette,
output:
md_document:
toc: true
rmarkdown::html_vignette:
toc: true
Secondly, copy the md file and other output files (like pictures) into your vignette folder, rename the folder for the output files into something else and make corresponding changes in your md file.
Finally, move your original Rmd file and rename the md file to Rmd, make changes to your md file (like adding vignette header) for it to look like an Rmd file for vignette. The new Rmd file will pass the R CMD check
easily and quickly.