Certified copy of summon sent to witness and other officials

You can seek any information on record of Public Authority unless the information enjoys exemption under Sec.8 or/Sec. 9

In case of judicial proceedings , unless the information is specifically barred, any Indian Citizen can have access to that copy.

You can file RTI Application and can seek the date of delivery of summons or even certified copies.  Your RTI Application or fees if any has to be as per your state HC rues and regulations.

All judicial proceedings are Public and open in Court (except ordered incamera in certain cases)

PIO can provide the information on record and may deny information stating that copies have to be applied as per HC rules and regulations.

Then if petitioner is a third party, he has to either appear in person or through Advocate giving Vakalat and the petition for CC has to be decided by that Judge in routine course.   There is prescribed time schedule

At any cost you can obtain the information.  Or /also  you can seek inspection and obtain copies even then and there, they will be provided.

RTI Route enables 30 days time and costs less than Rs.100/ and if court procedure is adopted, depending on advocate you may get within 3 working days and may involve expenditure of over Rs.500/

I agree with the right observation and proper suggestion/advice by Mr. G L N Prasad on the subject issue.  It is better to approach a lawyer, file a third part affidavit and vakalat along with a copy application seeking certified copies of the documents desired.

Most likely court will refuse. They jealously guard all information including decided cases unless no has been uploaded. Most of their websites are too far behind and not working.