Thanks much to all for your well wishes. Ends up mums are not liver or kidney toxic (in other words, they're not known to cause failure of either). Just really hard on the tummy and GI tract. He's had a lot of issues with his tummy since the beginning so I am praying that it heals properly. He has to be able to eat and drink or he will dehydrate, the organs will start to be affected, etc...
The vet had a shot to stop the vomiting. He finally kept down a tablespoon of special prescription soft food late this evening (first thing to stay down in well over 24 hrs.). He seems to be feeling better than this morning but is nowhere near acting like himself. The vet said it would take time and I need to watch for dehydration and lethargy. So far so good. Been keeping him warm and lots of cuddles. Last time he tossed his tummy there was no more blood. I'm hoping to wake up to a kitten again. He's acting like a 15 year old cat (like my other kitty fella).
Thank you all for your prayers, healing energy and well wishes. I just know it's been helping him. It sure has been helping me get through. I was so scared! Now I'm very hopeful. I really must share his life story some time soon.
Thank you, thank you, thank you again!!!!!