I have one of these but it's opaque black. I don't remember how far I got it. Have to try after an enema to clear a path. Any resistance means the end of action, generally.
OMG, I have a lube injector like that. It was a 2 pack on TEMU. You really gotta do a deep enema for this to work. Also once you can get it past the rectum/colon, it should snake in pretty easily.