Ask a medical specialist. This is too important for discussion forum anecdotes.
Most retina detachment comes from blows to the head, usually impacting the eye directly even with the eyelid closed. It's common among boxers and other fighters, or anyone who's suffered a head blow from crashes, falling, etc.
Whether bike rides can aggravate the condition would depend on many factors, particularly the condition of the roads (unpredictable) and choice of bike, tires, suspension, etc. Since the latter is controllable, I'd choose the softest riding bike I could afford that still performed as desired. My personal concern would be my neck -- old C1 and C2 injury from 2001, re-injured when I was hit by a car last year. I've made lots of incremental changes to my bikes to reach a compromise between comfort and performance, and will probably need to do so for as long as I'm able to ride. I may need to switch to bikes with suspension or that can accommodate larger tires to reduce the impact and vibration.
But your vision is more critical than my comfort issues from neck and shoulder injuries. You really need to consult a specialist.