My BP went without a meal for around 10/11 Months, so I wouldn't worry unless they are loosing quite a bit of weight. The first time I ever fed my BP a larger meal.. he went off feed for quite a while. Just offer a Rat every 14days.
The method I used to break my BPs fast was cracking the skull of the F/T Rat, which is where you stick a cocktail stick into the brain to expose blood.
You mentioned you was previously feeding American Soft Furs? have you tried offering an ASF? as they can usually sometimes imprint on one type of rodent.
Try pre-scenting the room, with a hairdryer.. maybe an hour/half hour before feeding. Also right before feeding you could blast the skull of the rodent to around 100f with a hairdryer then offer, see if your BP accepts, Good luck.. don't stress! we have all been through this!![]()