The only problem with anti-freeze in the icemaker water lines is that it is a nuisance to flush out in the spring. You get pink ice for awhile, and off-tasting ice for awhile longer. If you want to run antifreeze throu the ice maker itself, there are some tricks you can use to make the procedure easier/quicker, if you don't mind playing with 120v electricity. However, that is not necessary.
Norcold has ice maker winter storage instructions in your fridge owner manual under Icemaker Storage. It does not run antifreeze into the ice maker itself - just drains the line. That's all that is needed for the solenoid and the line from there to the ice maker. They say to disconnect the RV water feed from the solenoid (it simply unscrews). If you do that, you can pump antifreeze (or blow air) through the feed line without getting any into the ice maker itself. Leave the end of the line open (cover with plastic bag or wrap) or screw a hose plug into it after. You can then flush the line in the spring the same as the rest of the system.