Would the cage be inside? I ask, because thats not a very good outdoor cage at all, but you made it sound like the cage and pen would both be outside. I also think its a little small for 2 rabbits to share, but i personally like bigger spaces for my babies so i might be a little bias on size

Those are big rabbits. I’ve had a few california/new zealand rabbits. My bunnies are happy with a minimum space of 8x4ft. Any less than that, and they act up. I would put a guineapig in that cage, but not 19lbs of bunnie. I also agree that it is not a good outdoor pen. If that is the only size you can accomodate, this one might be more secure.
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That being said… It also depends on where you live. I brought my bunnies in because of flystrike. I let them run free in my fenced yard. For rain protection, I gave them pawhut boxes that were about 14″x12″x16″. I didn’t have to be worried about foxes or racoons, and for soem strange reason, owls never caught my bunnies. What I couldn’t protect them from – was flies. I coudl tell you horror stories about flystrike.
Another option is to get a doggy x-pen, and use a roof piece as a roof and floor. That way they pee into the ground and you can move them to a new piece of lawn each evening. I did that for a long time. By now I have probably have 8 x-pens. I stopped giving them overhead predator protection, and focused on providing a large mobile run for two separate pairs. Eventually I built them a 4×8 shed so they had more roofed space. But then I brought them inside… something I thought I would never do.
But back to your question, I’d be concerned that it is not predator proof depending on where you live, and I think it is a bit small.

My two baby Flemish sisters, a little less than 7 months old and at the 10 pound size, have a 3 foot by 6 foot pen in our living room.  The door to the pen is always open so they are free to come and go as they please.   They can at any time of the day, hop out and sleep somewhere else in the house (the bedrooms are closed).  They do spend a lot of time in their pen, but finding them asleep somewhere else is common..under the coffee table or under the dining room table.  The dining room table has many large cardboard boxes under it for them to play with, hid behind, and  EAT.    I’ve been pretty apprehensive, but eating cardboard doesn’t seem to harm them..the cardboard is just a snack since they are overfed with hay, green veggies, pellets, and treats.

About outdoors pens/cages….I was naive to think that bunnies liked to be outside when we first got an adult rescue rabbit.  I built an outdoor pen to keep her in during the daytime.  I had to build up the chicken wire walls since she was trying to jump outside…I thought she was just confused as to where she was a new rescued rabbit.   When she realized she could not jump out, she at first dug a trench in the ground.  She would lay in it with her ears down, and she wasn’t that visible…THEN she started digging a bunny hole.  An 8 pound rabbit.  She dug a tremendous hole.  The dirt she moved out would have filled up 1 1/2 wheelborrows!!! Astounding amount of dirt for an 8 pound bunny.  When she finished her hole, she would not come out.  She stayed in the hole basically 24 hours a day, with only brief excursions to eat.  This told me she was very afraid of being outside.  Catching her took time.  I waited until she came out to feed, and then a threw a pillow on her hole to keep her from diving back in the hole.  I caught her and for the rest of her life she lived in the house…cage free.   She had excellent litter box manners.  Her new home became sleeping under our bed.  She lived as a free ranging house bunny for about 10 1/2 years.

A bunny hole aside.  When she was in her bunny hole, the burrow hole was about 4 or 5 inches in diameter.  When in her bunny hole, she would backfill the opening with dirt, leaving only an approximate 1 inch diameter hole to allow air into the burrow.  For a predator investigating the burrow hole, it would appear as if the hole was essentially closed.

I agree that it’s not an appropriate sized cage, it’s much too small. I consider a cage that size too small for a single 7 pound rabbit, let alone a 7 pound and 10 pound rabbit. You’re also going to want something a bit taller so that they can stand up to their full height.

The others have covered the concerns regarding this cage being unsuitable for outdoor housing. It’s not 100% clear what your intentions are in this regard. If housing outdoors, I’d much more recommend a wooden chicken coop and run style hutch.

Rabbit society guidelines are a cage 6 times the length of the rabbit !!!!

Now in my case, the width of my own house is not 6 times the length of my rabbit !! LOL
But it gives you an idea of what the ideal should be !

A determined outdoor predator would pick that cage up, or turn it over and have them out in a jiffy.
Sorry, but definitely not adequate outdoor protection nor adequate size unless its just a transportation cage. As you know, rabbits love to periscope and stretch upwards.
For that price you could buy a second hand wooden cupboard/buffet and transform it – that’s what I did