Please help my son get his Autism testing

Hi my name is Amy I'm a single mother to my gorgeous sons name is Zachary he is 10, hes been diganosed with ADHD, ODD, anxiety. His teachers, school psychologist and his clinical psychologist have asked for my son to be tested for autism spectrum disorder which hes showing all the signs, to get this testing done in a few weeks I have to go private, which unable to work and on carers that's abit too much for me too afford my friend suggested a go fund me page so here we are. My son would be truly grateful as I have been trying to save up and get this much needed tested for a few yrs. The children's hospital atm has been our 2nd home as sadly everything is getting to much for zac to handle and without this testing my son isnt getting the right help he deserves, it is effecting his home and school life. If anyone could help we would be forever truly grateful. Thank you. ZAC is booked in for the testing on the 20th march with dr richard chrissy in midland