Infinite bubbles means that air is getting in during the bleed, either from unsound technique or equipment, a faulty hose connection, or a problem with the caliper or lever such as a faulty seal.
What I would do is bleed it exactly like a Shimano brake, except with the Magura fitting at the caliper end. Make the caliper the lowest point, level the bleed port, attach your funnel, fill it, plug it, fill a syringe and attach it, unplug the funnel, and push fluid through. If you get a bunch of bubbles, plug the funnel, remove the syringe fitting, suck the fluid up with it at the caliper end, and recirculate it back through until there are no bubbles coming up. If that point never comes (there are always bubbles), you have an air leak that has to be addressed. Once there are no bubbles coming up, plug the funnel, remove the syringe from the caliper bleed hose and attach a collection bag or bottle, and let it drain a little to see if any bubbles come through, making sure the funnel never runs dry. Then plug the funnel, close the caliper bleed port, unplug the funnel, and flick the lever around as you rotate the bike 45 degrees forwards and back in the stand several times, until no more bubbles come out. Then plug the funnel again and close the lever bleed port.
There's only one way of getting to a hose configuration on a mismatch system where all the hose fitting considerations are "right" or "as-designed" by at least some definition: use a third-party hose system such as Jagwire that enables you to have the caliper end use its Magura fitting and the lever end use the Shimano. Otherwise you're going to have at least an on-paper mismatch between either the barb/olive and the hose (where minor differences in the hose OD/ID can cause problems), or you're mismatching the barb/olive to the thing it's going into. I'm not saying this is definitely the problem, but it's one of the things it could be.