Advice for resignation from PSU (without medical clearance from the other PSU) - bond transfer from PSU to PSU

Respected sir /Madam, I have an doubt regarding resignation from my current job.seek your valuable advice.
I have joined one PSU in Aug 2018 now I got selected in another PSU and want to switch my job. The problem is that the latter company ask for relieving letter without providing me final letter of appointment which will be provided after medical verification.
In this juncture if I resigned from my current employment and unfit in medical test conducted by latter company what will be my fate in future.
second,Sir may I eligible for bond transfer from PSU to PSU in case I was not informed them that I am working in another PSU at the time of interview. Because I got selected in my first PSU after interview Conducted by second PSU.
Waiting for your valuable advice in this juncture.

Are you on probation in 1st PSU?
Please read the PSU rules on resignation to understand the whole process.
Their website would give links to personnel policies.
As far as 2nd PSU is concerned, you have to take a risk.
If you are sure there will no problem in medicals and there is no merit list for candidates selected and you will get the appointment,then think about it.
A bird in hand is worth 2 in the bush.Jobs are scarce in the present days.Think very carefully about why you wish to leave first PSU and join another PSU.
Be safe and careful in decisions but not fearful.