Definitely install a new dryer. It should not be expensive.

If it were mine, I would take the rest apart and flush the system completely. Actually, that's just what I did with the system in my W210, which needed a new dryer due to a restriction in the old unit. Lots of very fine debris came out of the evaporator.

It sounds like your TXV is a lot easier to access than mine. I had to remove the wiper system and some other stuff below it.