You are fortunate to have:
--Acknowledgment of original testimonials collected from you. Company can ask you to show the originals of the copies submitted by you but can not retain original certificates. You can prosecute the company and personnel who has signed the acknowledgment and is refusing to return the originals. Demand that these be supplied back to you at once in excellent condition. If these are mutilated, soiled, spoiled you can sue them.
--Not having the bond. Don't sign it. Rather you claim that you are being pressurized to sign a bond highly weighing towards company or give up your employment and source of livelihood.
--Realized in time, that this is the place for you. Separate by submitting notice of resignation and not resignation with immediate effect.
--You are not liable for the consultant's fee and hence you should not pay. If the company deducts this amount from payables to you, company and personnel responsible for processing and passing this deduction can be prosecuted.
Employee should record such demands/threats/coercions (audio/visual) for use at appropriate time in appropriate forum.
You may submit a gentle representation by letter addressed to good offices of your appointing authority, MD/CEO, Head-HR, Company Secretary covering all points and arrive at a conclusion that you are being pressurized and coerced, forced to give up your employment, source of livelihood, and submit to unfair demands at workplace and you are tendering your notice of resignation and seek intervention by good offices to provide relief to you. Post reminders even if by email ( with a copy to you).Your representation shall be a deterrence for posting adverse comments against you later.
You can always withdraw notice before effective date of resignation mentioned in notice.
If employer accepts resignation before effective date of resignation mentioned in notice, it can be termed as illegal.
In your case employer may ask you not to come to office, but you should (record audio or visual) insist for a written communication even if by email
Employee should remain amiable while in employment even under trying situations and try to resolve the matter in his/her favor. This is the quickest and easiest solution.
If you are not provided relief as sought by you, you may approach o/o labor Commissioner/Wages Inspector or approach a lawyer. Your lawyer shall rate your matter as a good case.