Either the catch can catches it or it gets burned up in the combustion chamber along with contaminating other things. Either way, you are loosing oil at an alarming rate. There would be zero proof the catch can is causing the issue, the catch can is only showing a potential problem occuring. If it were me, I wouldn't remove anything. They need to find the issue and not point to what is showing the results of the issue - the catch can is not the, or a, cause of this. Clearly the catch can is allowing flow otherwise it couldn't collect the gunk..
Now to save the potential hastle, removing it ifor a dealer visit sn't a bad idea either. Just tell them that it is going through oil ah a hight rate and then it is in their hands to track it down. I would deffinately make them relay everything that they test and check for and what the results of each was.
I'm sorry to chime in so much. Just trying to help.