Oh Kab there have been times when I could have written your posts. DS was diagnosed with ASD this year, at 5.6yo.
It's very hard to feel that way about your obviously much-loved child, and there's a huge taboo about talking about it.
What's clear is that there is some information which you are missing which could help you better understand what is going on.
So the first thing - which you are clearly already trying hard to do - is to get the referrals for assessments and checks sorted. In our area, we have a specialist health visitor for children with complex needs. They could be an ally for helping you to navigate the system, if they exist in your area.
My (embarrassing) tip is that it seemed to be much more effective to pick up the phone and sob at professionals than to send them perfectly reasoned emails. It seems to help them understand the urgency if they know that you are having a "mummy meltdown" (got that t-shirt...).
The other first thing is surviving while you wait for this additional information to become available to you. While all children need firm boundaries, the big secret that professionals never seem to tell us is that punishment doesn't really work for any child.
So, if you can, try out the tips and techniques that are mentioned on the special needs board. At that age, we had no thought of special needs, but we found the Playful Parenting book helpful for ideas on how to engage DS in doing what we needed him to do. We also started with a visual calendar.
The aim is to make things as easy as possible for you all. So only do things that you can manage, arrange stuff to make life easier for you, and try to notice triggers and likes/dislikes in your DD and work with them.
Definitely I would say let her go with her grandparents if they are happy with this. Take any breaks you can get. This is exhausting, and your DD needs you to be able to keep going.
If you can afford to see the private consultant again, could they recommend some techniques you could start trying with your DD?
Good luck, and hope things get a bit better for you soon
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