First international trip with my ADHD partner stressing me out

Hi all! New here. My partner 32M diagnosed with ADHD and I are going away to NZ in three days. Usually I would be so excited to leave the country (first time since 2019) but the lead up and packing has been stressful to say the least. Sorry for the upcoming rant. 

I feel like I'm planning a trip with a child. This is his first trip overseas since 2010 and I'm stuck in the position of having to explain airport security procedures even though they can easily google simple things like "suitcase limits" and "what can't I bring on a flight?". I shouldn't have to explain to a 32 year old man that if you wrap camera batteries in parts of your clothing that it might be inconvenient to repack or even find again in the future. I stress the "find again in the future" because he is loses everything and then if I can't find it it somehow becomes my fault or he gets ADHD temperamental. I asked him to please pack things in packing cubes/small bags to make it easier and he just started being dismissive and was plain rude. I'm always careful with my tone and try and be supportive and helpful, but playing nice seems to be biting me in the ass. It makes me want to cry just knowing that at some point in the future I'm going to have to deal with him losing something and not knowing how he will react. 

On top of it the whole planning has been one sided. Flights/accommodation/car rental you name it, all planned by myself. The trip has been booked since September and he never takes initiative for actual booking, just hyperfocuses on hiking videos of NZ without actually figuring out the logistics. Glad to see he is excited but watching 50 videos on hiking suggestions without writing a single one down and then having to watch them again with the same result with no tangible plan is bloody annoying. 

I'm exhausted and frustrated. How can he not take initiative, even for the smallest things, like writing his own luggage tag? Does anyone else have to be a parent for their ADHD partner when planning a trip? And does anyone have tips for working around a disorganised packer? 

Again, sorry if the above comes across as insensitive to people with ADHD. Flip side is that I am going for an ADHD test next month, and find it even more frustrating that we don't share the same forgetfulness rules. He loses track of time - I'll pick up the pieces. I lose track of time? Well then it just wasn't good enough.