Stomach Tumor

My 15 year old (golden doodle F1) girl was diagnosed with a stomach tumor today. Roxy has been regurgitating and throwing up for the last two weeks. After trying two different medications for nausea with no success, she had an ultrasound today which reveal a 3.5 cm mass. (Her blood work that was taken in January was very good.)
Even eating a bland diet of rice and chicken for a week, did not stop the vomiting; by day 5 she was vomiting again. I switched her food to Dr. Harvey and add an egg or shredded chicken to her meals. Also, I am adding olive oil, but will switch to a fish oil. I am giving Roxy smaller meals, 5 smalls meals a day instead of 3, and she has not regurgitated or vomited for the past two days. She has a good appetite.
Roxy had stomach bloat (Gastric dilatation volvulus - GDV) emergency surgery last year and she pulled through. It was rough goong, but she really fought hard to recover…she is such a trooper! Unfortunately, her arthritis worsened after the surgery. She was always an active dog, but could no longer do her 2 mile hikes.
Her hind legs are weak and at times she loses her balance or may plop down on her side. She still likes to walk to the neighbor’s house which may be 1/4 of a mile trip (there and back home). On the way back, I started using a harness to help support her hind legs because she gets tired. (Just wanted to give some history.)
The Vet Specialist said that if I wanted to proceed, we could do an endoscopic procedure to determine if the tumor is malignant or benign and the type of cancer. She thinks it may be carcinoma or leiomyosarcoma. The concerns are many. The Vet noticed her panting and thinks she may have golpp (Geriatric onset laryngeal paralysis and paraparesis) which could cause more complications such as pneumonia, larynx stops moving, increase panting and progressive hind limb weakness and imbalance. The surgery risks are infection, perforation, sepsis and re-growth of the tumor.
I asked the Vet Specialist what she would do if it was her dog, and her reply was that she probably wouldn’t put her dog through the surgery. She also said that she has no judgment in terms of what I would like to do.
I don’t want to be selfish. I love my girl so much; she is my heart. I want to spend as much quality time with her and make her comfortable. I guess I have made my decision.
Tomorrow I will let my Vet Specialist know how I want to proceed . It was helpful just writing all of this out. It was a lot to take in and process.
Are there any questions that I should consider asking the Vet Specialist?