In theory, there is a chance that his behaviour may have contributed slightly to it.
One of the lab tests they did around fasting was to give mice a very high fat diet, but only allow one group access to it for 8 out of every 24 hours. The group with restricted access ate exactly the same amount of food, but gained 29% less fat and were healthier than the unrestricted access mice.
Therefore, it is possible that if by skipping breakfast, he ate both his meals within an 8 hour spell that this did indeed have some contribution to his weight, but this would involve him not consuming any carbs or protein (including milk etc) outside of the 8 hour window.