YOU as the car OWNER need to take SOME of the responsibility on this.
#1 - Why didn't YOU double check the coolant's freezing point YOURSELF ?
#2 - YOU the car owner, should have INSISTED that there be a dipstick installed on YOUR engine BEFORE it left THEIR shop.
There is NO WAY any Hi Po engine builder will guarantee ANY Hi Po engine used in a Hi Po application. Many will work with their customers if it is OBVIOUS that any major failure or tuning issue was the absolute fault of their workmanship.