Not gonna lie, I used one of those adult tricycles on a beach trip when I was pregnant (I'm not fat, 5'7" and 123lbs) because I'm clumsy and uncoordinated as hell and didn't want to risk falling on a regular bike. The seats are wider than a standard bike but Amber would still need something specialized to support her.
She doesn't even need to bike, she just needs to WALK. She's made excuses about it being hot or there being bugs in KY... well, yeah, that's true. I live a few hours south of her in TN and all it takes is waiting until just before or right at sunset to take a walk. And there's also this neat invention called bug spray. It's useless trying to reason with her because she has an endless bag of excuses.
One time in a YN broadcast I asked her if she ever gets called out or made fun of in public and she says no. BULLSHIT. I used to weigh 185lbs and even at that weight there were several times that I had comments shouted out to me in public about my weight. AOn a bike or tricycle would be quite the sight for passersby, you can't tell me she wouldn't be made fun of left and right if she tried to go out in public like that. And that's really sad, honestly... feeling like you're a freak show act has to feel like shit.
Sorry for any PL-ing in this post.