Had the same problem on a 2011 Toyota Sienna. It took me 6 hours on the passenger side. It was not stuck in transmission, it was stuck in the support fixture. Definitely use some PB blaster, the capillary action of this material will pay off. It took 6 hours because every time I applied PB blaster, I let it dwell for 15 minutes. I used an air hammer. It was exhausting, but it finally came out. Make sure you have removed the snap ring.

After it is removed, when your putting the new one in, I highly recommend that you put a high quality grease on the support fixture. Also, there are two small set pins on the fixture when you remove it from the engine block. Remove these pins and don’t reinstall them. This saved my ass the second time I had to remove the axle for replacement. It was again stuck after two years of use. Instead of and airhammer the second time, I simply unbolted the fixture, and removed the fixture from the axle on a table clamp.