Chance of Success in applying for widowed mother under 65yr

[fj2020]

Hi Guys,
I understand that applying ILR for a dependent parent is getting quite hard. However when I contacted a few immigration lawyers, they seemed to be taking it as a piece of cake and assured me that it could be obtained(can't really trust as for £1000 fee they would get, they may give too much hope).
I'm actually a skilled migrant on ILR , my widowed mother is 54yrs old and is on her own in Pakistan. Her one daughter has got married living in a different city and my brother lives in dubai. I earn 50+k and wish to bring my mother here.
I've two choices, either to bring her on visit visa and keep applying visas until she get 65(when i can apply more easily under dependent category), or apply ILR now. As in visit visa application, one has to prove more ties to his/her country and in dependent category its completely opposite; I need expert impartial advise on which route i should choose as applying in other category if application under one route is rejected make matters suspicious because one takes a complete u-turn about ties in homeland.

under 65, a dependent could be provided ILR only under Exceptional Compassionate Circumstances. My mother is suffering from clinical depression due to her loneliness for which i can provide medical reports etc. Financially, i've been supporting her completely and have record of 1yr financial transactions. have accommodation etc.

would really appreciate if some people can guide about most appropriate route, any idea what percentage of cases are approved by HO in this Exceptional Compassionate Circumstances category??