Cracking in Tailgate

So, recently I got a bunch of alerts on my 2015 trail hawk to service my parking brake, cruise control/front collision, stop/start system and said my 4wd was unavailable. After taking it into the dealership, it turns out the e parking brake module was corroded. This leaking is coming from where the tailgate attaches to the car I have attached photos of the cracks. After looking further into it, I have noticed this seems to be a very common thing with the Cherokee model. I currently have a case going on with Jeep about this as my repair for their error is over $1700. I am looking for more people who have the same cracking in their vehicle.. this is also a warning to check and seal your crack before it gets as bad as mine. I would like everyone who has this cracking to attach a picture to help me prove my point to Jeep.