I had GD and had a homebirth with my second son. However, we(my midwife and I-I work for her) were in total denial about it and it was uncontrolled. We didn't really believe in GD...however...
An hour after a normal meal (as in not a lot of carbs, no sugars) my number was 154. I got tested because I was just dumping sugar into my urine.
I had a 12lb 12oz baby who was a 5.5 minute shoulder dystocia, he had APGARs of 2 and 10 and needed resuscitation. It was terrifying for everyone in involved, particularly for my partner.
My biggest fear was fetal demise. It can be a risk of GD and it should be taken seriously.
If managed properly, it would be perfectly fine to have a homebirth.
I would have walked a mile a day,seriously changed my diet and tested my blood sugar if I could go back in time. I cut back on sugars, but still ate them as well too many carbs. I ate a very healthy diet, but treated myself to goodies too frequently.