I agree the snowflake and reindeer are not very well thought out or charted correctly. What a shame.
If you can print out or photocopy the pattern you can modify the chart by just taping the correct snowflake on top of the main chart as it symmetrical the print version can be just turned upside down to make the correct half of flake.
I would redo to the lower sleeve, but I wouldn’t chart it out, just photocopy cut and stick. You could just ignore the reindeer, leave the snow fake, or take a copy of the front chart and use the reindeer off that to just stick on the chart in the right place. Another option would be to ignore the reindeer and flake and replace them with a tardis.
I’m currently working from 2 charts each made up of 3 or 4 or 5 copies of the original cut up and taped down, just make sure the grid aligns.