I'm a Red Hessian trying to get the right tech, but the ID is not valid and the only IDs selling are Freelancer and Recruit and it reduces my power to 75%. I know I cant get the Red Hessian ID because I am not friendly enough for it.
The recruit ID should still give you enough power output to do some missions for them, but if that is not enough keep an eye out for some Hessians in game and ask them for some help repping your ship. Anyone who is already a Hessian can run missions with you to help you along, or you can get some bribes for people friendly to the Hessians or even one for the Hessians themselves.
If you want to, you can lower your rep with them (either through good old-fashioned missions for their enemies, by aborting missions, or by using "/droprep"), then try to get a double bribe in. That should bring you up high enough to buy the ID.
Of course, doing missions for enemies isn't really in-character for role-playing and "/droprep" costs money (I think), so your best bet is probably to either do missions for the Red Hessions or drop your rep by taking a couple of missions but aborting to try to get low enough for a bribe.
The recruit ID only exists to help you set up your character. As long as that is all you are doing with the recruit ID there is nothing sanctionable about it.