Hey there, fellow new spider owner here! I read a lot about the spider morph before deciding on a morph, and some people seem to reckon that a wobble can get worse depending on the level of stress. I noticed my snake was wobbling a lot more during the first week in her new home, but her wobble has already calmed down a little bit after she is settling down in the second week.
From what I have read, it can be difficult to know the severity of the wobble until you spend a longer time with the snake, and some people seem to think that a wobble can vary at different points in their life. For instance, a young non-spider morph may still be off with strikes simply because it hasn't perfected striking yet. Add a wobble to the mix and you get a pretty clumsy snake.
For some recommendations, I would suggest heating up the prey if you don't already, as maybe your spider is also confused by the heat signature of your hand. It may be that she also becomes nervous if she smells you in the RUB, causing her to wobble more, which in turn could explain why she finds it easier to take the mouse from the RUB.
I really hope her wobble does improve for you though, good luck!