Planned privileges

My near 14 year old daughter who has suspected Asperger’s and RAD has been showing signs of quietly adjusting behaviour when I keep an objective log of behaviour quietly and then discuss away from the moment – as she gets overwhelmed with my talking to her.

Would you ever recommend using communication cards in the moment to help instead of talking- as my talking to her is one of her big triggers to feeling overwhelming anxiety and rejection ?

Also she’s accepting that she has behaviours that she’s choosing and self correcting some that she chooses.

Question:
My husband is planning a trip to see his elderly mother in the UK and wants to take her and my son. It’s one of those key life memory moments. We want to send her but it’s pushing the boundaries of our finances. Is it okay to just sit her down and say “honey your behaviour just hasn’t been on track this last month even knowing that we were going to take you & while you have said “I will be good” your record shows you haven’t – so you we can’t justify the cost. You have chosen to say you don’t accept the family standards and you haven’t earned the privilege”

Or is it more important than ever for her to have key family memory experiences?

I am pretty sure she will be beautifully behaved on the trip as her main issue is with me not dad & we hope being with her grandma would give her some identity and belonging…AND I don’t want to be manipulative, but it’s a short time we have to decide AND she’s not showing signs of wanting to surrender to family roles and standards – how can we navigate this? And not make it look to her and the rest of the children that her persistent bad behaviour is rewarded??