the possibility is there, but minimized because the dipstick tube is ribbed on its exterior which mates with the interior of the pcv grommet. Because of the ribs, you have to walk/work the sleeve into the grommet,.. then when the intake tube is inserted, i had to lube it up and when inserted, there's a positive "shump".
I'll keep my eye on it and post immediately if it pops out.
Ron