Your case is hard. You have only a limited amount of time to add the other parties, and unfortunately, a federal complaint is not something that is easy to put together.
I do not honestly think you have time to get the Amended Complaint completed, file it, get a citation issued, and serve it on the new defendants. You cannot serve it yourself, it must be served by a certified process server. It is often an expensive process.
If you have spoken to many attorneys and no one is interested in taking your case, then this might be indicative of the strength of your case, and you should really consider whether it is the wisest decision (and worth the continued stress) to press on in this case (or attempt to add more defendants to the case) when it might not be a winning case.
I cannot truly assess the strength of your case in this forum, and this would only be something a local attorney could do for you.
That being said, there should be a section on your complaint called "Parties" where the defendants who are already in the case are listed. You need to add the new names of the new defendants...as follows:
"Defendant Jane Doe is a resident of ________county and may be served with process by serving her at her regular place of business ________-(address).
"The City of _________ is an incorporated city in the state of _________ and may be served with process by serving the City Attorney at ________(office address).
Then you have to have additional paragraphs which are separately numbered which detail the acts that the new defendants did which were illegal and why they are illegal.
In short, this is really a technical process and is extremely hard to do for a layperson with such short time.
Here is an example of an Amended Complaint.
I wish you the best of luck. I would continue calling "Plaintiff's" attorneys or "civil rights
" attorneys and try to find someone who will take your case. Even if you miss your filing date, it sounds like you have a lot of the parties that are probably responsible for what happened to you.