I remember having to give one of my cats a bath after she went missing and then returned a day and a half later covered in stick sap like stuff, I think she may have been stuck up a tree. Anyway we tried to leave her to clean herself, but as she couldn't, we had to bath her. She didn't appreciate it one bit! We used the shower attachment to wash her, which was easier than trying to lower her into the water, bad idea! But as she is very gentle natured she did not try to claw too much! She laid in front of the fire afterwards to get herself dry and went all fluffy!!
Hope this does the trick for your cat, or you may have to do it again!!!
Cheers Sue