Complitely counter productive and will only lead to more stress, which means more refusal.QUESTION 2: should I try to put her in her travel tub for feeding? I know it's recommended to feed them in their enclosures - and that is definitely my preference! - but if she's lived in a tub and been fed in a tub for over 2 years, could that be the reason she's not eating? Just not comfortable enough in a glass terrarium?
The truth be told the issue you are experiencing is pretty typical with adults, I have purchased and received adults on loans and more than 50% of them will go on food strike anywhere between a month to a year.
So what can you do.
1# Try to emulate the setup she used to be in prior to you acquiring her (same temps, same type of enclosure, same substrate).
2# Limit your handling to maintenance.
3# Offer less often.
4# Be patient.
If she was eating F/T do not offer live, unless you are willing to do so for months or years to come, usually an alternative prey is not the answer.
As for mentioning this to a vet be careful many vet are lacking the hands on experience and understanding when it comes to this species and will suggest all kind of crazy things such as assisting, force feeding, tube feeding, x-ray to see if there is an internal issue etc, if that is the case walk away.