Well from your description of what your frying the fat is coming from the filling, and to be expected. The time depends on the thickness of the rolls, impossible to tell you a time. 350f is a good temp for filled egg roll wrappers, but the time seems very long to me. Many questions, like whats the size of your fryer and its recovery time, how large a load are you putting in the fryer. Start by making sure your fryer is at temp and make sure you use a small load in the basket, pull one after 2 min, 3 min, etc. You need to test until you find the proper load size for your fryer and the temp you’ve selected.
If you still think its from the fryer oil fill some wrappers with only veg, like bean sprouts and see what the results are.
There must be 10,000 or more hits on doing fresh fries, so do a bit of searching, and testing on your own with your equipment too many variables to just pop out an answer