I've just cast this chart and checked the positions with Whole Sign Houses, like you I have 3 planets in the 12th (using the classical (& vedic) 7.
So the question is really, have you got an accurate birth time? I've seen a time of 06;00;36 claimed, which would put these planets in the first BUT I have no way of verifying this, as I've also seen the same time quoted as you quote. The issue comes down to checking very carefully both the sources that claim a 09:06 birth and the sources that claim four (?) planets in the first and the House systems they claim.
Given the time distance and possibly the lack of accurate birth recordings at that time, I'd guess that you won't resolve this (but it's worth trying). It's also possible (given the importance of Astrology in India) that the time was 'massaged' to create a favourable chart.
Welcome to the world of Astrological archaeology LOL
Let me know if you find anything substantial, either way. In the mean time I'll cast two charts one for each of the times quoted above.
PS Astrodatabank quote a time of 06:22 and another site is claiming 05:30 also using Placidus cusps.
Now you might try some quite complex rectification but even then there's no guarantee. So you are let with pondering several possible charts, one or more of which might appeal to you but unless you have very detailed and personal knowledge, you might be swayed by your prejudices, rather than anything objective (assuming it's possible to get to objective data).
