Hi Jan,
I'm sure you will get many replies as this issue is debated quite frequently here on the forum. The first thing I would suggest is to discontinue the bolus feedings by syringe. Get a feeding bag and let the feedings SLOWLY drip into the tube. Many people cannot tolerate the bolus feedings.
Also, you may need to go with a different food. You didn't state what Jim was using, but I know Ensure sometimes is not tolerated as well as some of the other foods. My daughter did better with Nutren. Others have done well with Jevity, etc.
When they did the tests, did they check to see if the stomach emptied properly? In Heather's case, some of the food stayed in her stomach instead of going through her intestines. As soon as she moved, she would vomit. If this is the case with Jim, they should prescribe Reglan (metoclopramide). It helps the stomach to contract and empty completely.
Whatever you do, don't let the doctors shrug this off. It took us much too long to get this figured out and Heather lost way too much weight. She was vomiting for 2 1/2 weeks while the docs screwed around.

Make it a priority to get them to address this issue ASAP.
Good luck,
Rainbows & hugs,
Rosie