SP stoma is still leaking...

Since last December, my bladder has been leaking around my stoma. I have changed medications from Ditropan 5-10-15mgs to Myrbetriq 50mg and now to Vesicare. When I changed to Myrbetriq, I went about 2 months without leaking, but started leaking leaking again it hasn't stopped since. I'm currently taking Vesicare 10 mg twice a day. I was taking it once a day but it didn't help, so my urologist bumped it up to twice a day... and its still leaking. Bladder infections have been ruled out as the cause and two cystoscopies revealed nothing out of the ordinary. I asked my doctor about botox but he said he didn't think it would help in my case, but has offered no other ideas on fixing the problem. I asked about bladder enlargement and he said it was an option but apparently I'd have to travel elsewhere to have it done.
Are there any other options and if not, how well does bladder enlargement work, and are there many problems with this procedure? I've been doing bed-rest for about 19 months due to pressure sores, but they are healed now and the bladder problem is what I need to get solved before getting back in the chair again.
My catheter drains well but I'm still leaking like a sieve. I need help...

SP stoma is still leaking...