After stroke nausea, consulted gastrologist and neurologist, what to do now?

So here is the story: (Excuse my lack of knowledge or usage of terms)

My mom had a stroke a few months ago (aneurysm) and the cause was a burst/rupture in the artery behind the neck leading to the brain.

The Neurologists first attempted to place a coil to close the rupture, by accessing the body close to the waist area. That was unsuccessful so they ended up closing it up via local surgery, open surgery accessing through the skull.

She was recovering for about a month and she started feeling weakness, dizziness and nausea, so she was admitted to install a "shunt"

After the shunt, she's been constantly feeling nauseous and cannot contain any food, anything she eats comes back out orally (vomiting)

So she was admited to the neurologists and they said that there is nothing wrong with their "shunt" or the clip

They advised her to go to a Gastrologist to see if the passages were closed or restricted. The result came out as nothing obstructing the passages. The doctor suggested using suppositories but that has not helped her nausea.

Now what should we be looking for? Neurologists and the Gastrologist said that there is "nothing wrong" so what would you guys suggest? getting a second,third opinion?

Her current symptoms/status
-She must stay laying down for her not to feel nauseous
-when she sits up she feels nauseous
-when she walks around is a bit better but eventually feels nauseous
-sleeps a lot, very tired
-not really under any meds currently, they had "valium" and suppositories but they weren't helping.

My family and I really don't know what to do/where to look. What are your guys suggestions or inputs?

Any help is greatly appreciated.

Thank you,