Megalodon carb question

I have an odd situation and was wanting some thoughts on this. I bottled 5 gal of the Megalodon extract kit 6 weeks ago and tried my first one last night. Flat as flat can be. I stored it in a dark room that is usually in the 65 degree mark. Also, I swirled the bottles about once a week. Now, this is where it gets strange, I gave two bottles to a friend and told him to store them at room temp and swirl once a week. Well, he stored it in his fridge the whole time and didn’t swirl once. He sent me a pic and his brew was totally carbed with a huge head when he poured it. How is this possible?

What was your method for adding priming sugar? Did you add sugar solution to the bottling bucket? Did you use carb tabs? Sugar directly into each bottle?

I added my priming sugar to the bottling bucket. I actually stirred the wort with priming solution while bottling.