I've never had to assist feed. But from all I know it's an absolute last resort.
And as Deborah often says: " you don't assist feed an animal that already knows how to eat".
...and in Deb I trust.
Since the snake came to you at 50 grams and has eaten twice in yoyr care, I would advise against assist feeding.
I don't know enough about the subtleties of their care, but Bredlis are mainland Australian carpets, and Irian Jaya is an Indonesian island... maybe their husbandry shouldn't be identical?
Maybe try making some husbandry tweaks. What works for one locality may not for the other.