Transmission stuck? Honda odyssey 200 000km

[HotDeal]

my gf's family Honda Odyssey is still strong and runnin' very welland it's near 200 000km since 2003.transmission oil was changed recently, b4 replacing the transmission oil,it was at the "min" level....so it's good we got that done!however we discover a new problem, it's very stiff from shifting 'D' to 'D3'cuz we were comin' down hill (at blue mountain) we tried to downshift,and it was near impossible. i stopped the car on the side and ittook many strength and effort to go to D3...feels like i'm gonnabreak the shifting rod (behind the steering wheel)few shops we visited and claims that the transmission needs tobe rebuilt (near $2000)neverthless, one shop stated, it could be the cable.....andthat can be easily replaced.anyone know wat's goin' on? please advise!