Do you have information on the ingredients in it? (like soy, wheat, whey, etc.)
What about the nutrients it provides? (like specific amino acids, vitamins, minerals, etc.)
Knowing this will help to answer your question better.
In general, protein powders used alone in a shake made with water will be lightest on your digestion. Taste & texture aren't always palatable, so people will add things to it: berries are a popular add-on; leafy greens is another popular add-on; both provide much variety.
Perhaps in her suggestion she is thinking along the lines of easing your digestion while the ulcer heals. That can be done first by reducing or eliminating foods that are known to irritate you: spicy foods, high-fiber foods, and foods you are allergic to are common irritants. Digestion can be eased also by making foods more liquid, or softer, such as with soups and purees; thus breaking down the foods prior to eating them. The more liquid they are, the less the digestive processes have to work. The less work in digestion translates to less acids or other by-products that would irritate the ulcer and inhibit healing.
I would suggest you discover the ingredients & nutrients in the suggested protein powder and then research how they would impact your body.
Might also be wise to look at the cost of her suggestion and compare that to other products with the same ingredient/nutrient factors.
(Edited to add this) Amway produces more than one type of protein powder. So perhaps you can get the information about all of them to make a more educated decision.
In addition - there are many healthcare practitioners that support and/or promote specific products. In most cases these people have done their 'homework' and researched the products enough to feel comfortable suggesting them to their patients/clients. Ask questions of your provider to determine this for sure. As with anything in this system, there are those who are only doing it for the money they get in it and we each must do our own investigation to attempt to avoid being taken advantage of.
And, if it matters, I am a former Amway 'agent' (as you put it), and a former Shaklee distributor as well, and currently working with Melaleuca - The Wellness Company. I've researched a lot of protein powders over the years, including many others not produced by any of the above companies.