You're right that he didn't say anything explicitly mean about or to Britney, and we all know The Sun likes to take things out of context so we should probably wait until we see the full interview before judging him too harshly. I don't think there was anything too crazy happening at the wedding because afaik Britney doesn't drink or do drugs, but it sounds like the kids didn't want to go because the rest of their family or father weren't invited.
I think the main problem is the way he's trying to convince everyone that both Kevin and Jamie are great guys who've only ever had Britney's interests at heart, when everything she's said is pretty much the opposite of that. Imagine if your father literally had you locked in a facility against your will, pressured you to take medication, kept you on a pittance of a wage, controlled what friends you were allowed to have and whether or not you were allowed to have children, and then your own child tried to tell the entire world that he was a great person who was only ever looking out for you. I can 100% understand why Britney's upset over her own children not believing her story and siding with her dad over her.
My thoughts exactly There's definitely something fishy going on with this whole relationship. I think it may be another case of following the money to see why the kids are switching their allegiances so quickly