My dd has silent reflux - she sometimes vomited, but not after every feed, and not an unusual amount: just lots of pain. I had no choice about the camera test: she has a 'floppy larynx' (laryngomalacia) and the only way to confirm the diagnosis is via laryngoscopy...and no one would prescribe meds for the reflux without a formal diagnosis.
In her case, she needed treating not just to reduce her pain and stress around feeds, but also because the acid reflux made her breathing worse and she's already had bronchiolitis on top of her somewhat restricted airway. But as someone else said...different baby once the pain is addressed, and I think it would have been worth it for that alone.
She was given Gaviscon by the GPs, which was pretty useless because its main function is to limit the vomiting - which wasn't her problem anyway. Now she's on Ranitidine and Domperidone, and although still windy, a lot better. Wind we can deal with - reflux she was inconsolable.
For the OP, I'd push for giving Gaviscon a go - it might help the vomiting, it ca'nt hurt (apart from causing some constipation!) and you can always stop it if it doesn't help.
And for anyone faced with the 'camera test', FWIW it was a teeny tube down her nose and she yelled for a second then was fine...it was very quick. Yes its invasive, of course, and if I could have avoided it I would - but as dd ended up on nasogastric tube feeding, cpap oxygen and an IV drip for her bronchiolitis it didnt' seem like too much if it could help us avoid that again. And she tolerated it really well. That said, she is only just nine weeks old...maybe an older baby would have a harder time with it, I don't know.