To answer your questions. Please note that I am not a urologist, so you may want to consult a 2nd opinion for further information on your questions.
1) It would seem that this is a reasonable course of action. It is likely that the catheter has to stay in to prevent the scar tissue from causing another obstruction.
2) I was not able to find date supporting an increased incidence of bladder neck obstruction with silicone catheters. It may be certainly possible that the groove presence may have stimulated scar tissue to form around it.
3) If there is any doubt or concern about the care you are receiving, it is certainly reasonable to obtain a second urological opinion.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Thanks,
Kevin, M.D.