What else could be causing car not to shift?

I have a 2001 Dodge Stratus SE 2.4 manual
transmission When I bought the car used I
was told by different mechanics I needed a
tuneup just for good measure, and because
the car had sat for a year. Car was difficult to
start at first so per the pros I replaced
everything from sensors to having gas tank
dropped cleaned etc, Then was informed that
it was the throw out bearing so I replaced the
clutch. Now when I try to shift it won’t.  I’m
being told it’s the transmission which was fine
before the clutch was replaced.  Are they
right? ,could it be something more simple? or
do they just like that I’m a gullible blonde who
wants her car to do more than look pretty in
the driveway so she Will keep doling out the
cash? Please help!