I "believe" there is an idea to use the TRTO facility to train/qualify candidates to have a portfolio of crew to offer to other airlines , if, obviously, the candidate wishes to have his/her services hawked around the world.
TRTO is a revenue, and anyone accepting to accomplish/pay for a rating without a contract in the hand , does so at their own discretion.
On this basis, although they may derive some benefit from it, what airB propose, can hardly be viewed in a negative light, if they don't need you, don't promise you anything, but still, you want to do the rating. . well, your decision, and anything they do to help you become employed is a +, and not a - , in my opinion.
As regards the post from F50 Driver, I will respond more fully shortly, still time for a couple of beers in Riga
however, in brief, whilst his opinion is, I am sure , valid for his experiences & feelings, it is not the only viewpoint
suffice to say, mine are a whole lot more positive.