Help kobi with emergency surgery

Kobi is my friend Cassie's dog who for has been rather sick for some months now and over the last couple of weeks he has rapidly declined. Cass to this date has done all the tests under the sun which have cost her an arm and a leg. Kobis emergency surgery on tuesday which is another $2500 just to do a biopsy, everything is leading to a large tumor from part of his intestine to his bowel. After this exploratory operation on Tuesday he will then need further care / surgery. Kobi is only 7 years young, Cassie and her dad went and picked him out just after he was diagnosed with severe early onset alzheimers, they became best buds as kobi kept her dad happy and entertained through his illness. Her dad no longer knows who we are and so having kobi, keeps her dad closer to my heart. There is so much of her dad in kobi that it absolutely breaks my heart to see them both soo sick. Her dad has no chance of a cure but kobi does. She is stuck in a hard place financially as we all know there are other bills to pay also, the vet has high hopes as he is still young but if i cant afford the next couple of operations then its been suggested i might have to let him go. He is her everything! So anything would be grateful, thank you so much for taking the time to read this