How do you handle the exceptions?

From Owen Strachan in Children’s Restrooms Are The Next Front Line In The Gender Wars:

Sex differences are not controversial. They are coded into our physiology. According to scientists like Bill and Anne Moir, men have on average 1,000 percent more testosterone than women. Women generally have much higher serotonin levels and speak thousands more words per day than men. Men and women are anatomically different in some obvious yet crucial ways. We cannot produce children without respecting the natural design of our bodies. The gender-fluid society may sound promising, but when applied at the granular level, it shows its obviously impractical nature. Like facts, bodies are stubborn things.
You don’t need to be a snake-handling religious nutjob to see this. ... You just need two eyes that function and a brain amenable to common sense.

What Christians by and large don't seem to deal with are the exceptions. As I mentioned before there do seem to be exceptions - estimated around 1 in 1000 - where its difficult at birth to determine gender, and as I outlined there Denny Burk has recognized the existence of such individuals, but his conclusions seems to also fail the common sense test:

... even in those cases, those who have only one or more X chromosomes should be treated as female, and those that have a Y chromosome should be regarded as male.

This means there are a certain set of individuals - those with complete androgen insensitivity - who would historically have been recognized as female and who have bodies externally appearing to be female that Denny Burk has determined to be male. (I tried to contact him a while back but received no answer and the website of the organization Strachan heads also fails to address this topic. I don't recall any Bible verses on DNA testing being the definitive way to determine sex - was Denny Burk the recipient of some sort of authoritative divine revelation or else on what other basis can he mandate that others share his conclusions?)

It's one thing to recognize the reality of sex differences. It's another to figure out how to address those whose cases would seem to be exceptions. (Single occupant bathrooms / changing room stalls / showers would seem to be an option).