Rabbits hard to understand

Hello all. I recently brought home a young female rabbit to bond to my year old male. He is a free range bedroom bunny and I put her in an indoor cage with c&c grids for extra space to help keep her seperated but so they could sniff each other. He seemed very curious in her but for the most part they ignored each other. Cleaning, eating, some chewing on the bars and sniffing etc. It seemed very positive.
I let them meet in neutral territory (dining room) a couple of days later and the usual happened from my older boy. Mounting, grunting, chasing, small nips. He seemed a little rough as she squealed a couple of times in mounting but I pushed him off and after a moment she seemed to relax. He cleaned himself and sprawled out next to her. The second time was more of the same, a little rough, he kept trying to shove his head under her tummy and head. Peed on her, more mounting and grunting. No attacking but she seemed a bit intimidated.
Today I thought I'd try them in the bathtub. No mounting but he keeps trying to shove his head under her and give her nips and she doesnt seem to appreciate it too much. Shes frozen. He cleaned himself a bit again and then flopped over next to her.
I feel like hes waiting for her to groom him but shes very timid, especially after him being a bit of a brute the past few meetings. I'm writing this as I'm watching them and they are both laid down. She has her eyes closed and hes laying down opposite her. Both relaxed.

But I'm so confused. He's fine with her, but he seems so rough with trying to get her to groom him I feel like she's scared of him and I'm scared he might hurt her. I don't know if I should keep up with these meetings or just try and see how they do together in the bedroom.

She is a place that she doesn't know, with things going on around her that she isn't used to, and a change of routine from her previous home. Sounds like they just need more time to settle.

Shes quite happy and confident in her cage. Binkies and munching on hay. Shes just intimidated by him. He is a lot bigger than her and hes typically a grumpy spoilt boy. I've tried letting them out together in my bedroom where they will be living to see how he reacts and hes been a bit nippy and rough with her but now hes left her alone. Shes in his litter tray munching on hay and hes just outside laying down. I feel like he accepts her, hes must a massive grump... I will keep a close eye on them to see how they manage for today

It sounds like a "normal" bond to me. He has to show his dominance at first then they will settle down hopefully. As there has been no fighting this is a very good sign and I would try to keep them together now. If they are in the bedroom I presume she would be able to dodge him when he chases, he will soon get fed up with it. Let us know how they get on.

Thank you. My first bonding many years ago was incredibly easy. As soon as the buns (in my sig) touched noses they fell in love lol. I guess I was hoping it would be that easy for these two but just my luck lol. I am just worried by how much he wants to nip her and shove her around. She runs away, or hunkers down, and he gives chase for a second but then loses interest. She acts a little panicked by it but then quickly starts exploring and eating again. I guess he is just a very dominant grump and hopefully he will learn to relax. There is no grooming as of yet, I tried dabbing a bit of strawberry jam on their heads to encourage it but that didn't seem to work, just made us all sticky lol.

They seem very relaxed so I reckon they are going to get on very well. How old is she?

10 weeks so still very young. She seems very happy here when shes not being pestered by my boy lol. I've been letting them roam free for the day and they've finally eaten some hay together without him getting nippy with her. Fingers crossed it wasnt just a fluke

Hmm? I'm in no way any expert in bonding whatsoever. So all I can offer is observations and comparrisons.
Firstly, in my opinion I agree with Shimmer. Your new female is having emotional overload at the moment. She has been used to an environment and home, and now all that has changed so she has to adjust to new smells, strange sounds, routines, and everything else. She has to tune in to her new world. She doesn't know this is her home now - it's a place she has food and warmth but she has to learn that she is safe and warm and has food. She also has a bun friend which she has to adjust to.
I don't know if your male bun has been with any other rabbits or not, so he also has to adjust. And just as we hoomans are, some are more confident than others.
Your male - this is his home. He knows you and everything around so he's uber confident.
Looking at the video and reading your post, you seem to be doing everything positively and correctly. You're reacting when you need to and their language from what I can see, is incredibly positive. Rabbits need to resolve their heirarchy and it would seem like your male is asserting dominace over your new bun. It can be a little rough but it's something they will work out.
I've recently gone through similar - my new bun (male) was introduced to my female who had recently lost her husbun and she was quite dominant. When the new male arrived (smaller), he had never lived with another rabbit before and was extremely excited but I had some additional complications. Anyway, the new male is now slightly more dominant to my female and she grooms him and he does the requesting. He behaved not unlike your boy is and we are 3 months in and they are settled but not as close as the old bond was with my female and her bridge bun.
I would say continue as you are, and montor closely like you are, and time will be your friend and they will grow together in their own way.
Good luck and hope this helps
Craig x