I had it wrong in my initial email. The problem was with the 10bar ports on their housings.
Also there are benefits to the olympus housing. The nauticam was going to be around $1700. There's not many local vendors for this gear and if you order it online you get hit with import taxes when it goes through customs. The cost of the olympus housing was under $1000. Also my brother has the Epm1 and housing so being able to share ports is another plus.
I know one is aluminium and the other plastic but I've had the zx1 housing for 2 years and it's been fine and I reckon the omd housing will hold up at least as well.