I have an adult albino female TPRS that is doing the same thing.
Here is what Don Soderberg told me.
First, you have to give the snakes atleast a week after a regurge before refeeding. This is VERY important. This is because the stomach acid and natural stomach flora has been emptied and needs time to build back up in order to even have a shot of successful digestion.
You can tube feed them with a red 16" feeding catheter the following mixture that works 98% of the time for Don.
Mix:
1/3 jar of ground turkey baby food
2 drops of Nutribac paste
1 tbsp Pedialite or Gatorade
3 insuline units of vitamin B complex
The aforementioned is very digestable and works 98% of the time for Don without a regurge. It is recommended if the snakes have puked more than once. It is meant to get them back on their feet.
After about 3 feedings of that, try a pinky head, then a pinky body, then work your way up to a whole pinky. All of this with 3-5 day increments.
Remember subocs, as a species, prefer smaller food items. Even most adults will usually take hoppers but refuse adult mice.
Hope all that helps!
Dusty