These things just tend to be problematic. Pulled the one in our last TT out. And pulled the one out in the TT we've had for less than 2 months. We have no idea how it even happened.
With those T hold-opens, a big gust of wind can cause it to pull the screws out. You can get the T style that hooks on rather than push in, but may be a worse problem with pulling screws out. They look like this: RV Designer Angled Door Holder
Never had the type you have and don't no if it's more or less of a problem? Biggest problem is having those dang screws stay in place. If you can open the door 180 degrees against the sidewall, that might work better and I think there are one or two different style of hold open latches for that application. But if you have an awning support in the way, that's not an option.
You *could* install a gas shock, but I've read that those can eventually cause some serious damage to the door or frame. I've seen them mounted at the top of the door and at the door sill.
I think what I am going to try and do is take the door apart and put some wood backing inside to hold the screws. The doors appear to be put together with screws and hopefully it's just a case of disassembling it...
Not sure why the manufacturers don't do a better job. All it takes is a moment of forgetfulness that door is latched on and you give it a tug and whamo, it's damaged. You can't just put bigger screws in because it can happen again.
Don't know if this helps, but there you go...