well...
i shot a few dental xrays (fits perfectly over a 135 window
) using ei12~25 in daylight and also made some contact copies from negatives on them.
developed in id-11 stock under constant observation/agitation using a french fulton MX991/U flashlight (those vietnam L types), moded with a modern 5-led china reflector, with the white difusor and red filter on.
never had any issue with the safelight and i did inspect closely the development (i mean CLOSE, like less than inch from the torch) and never noticed even a slight fogging.
so i dare say these little bastards are quite resistant with red light. so much that i have to expose them for 16min under c-41 negs a few feet from a led lamp to get them some proper exposure due the film orangeness whilst bw films is less than 10sec under the same light/distance.
what i think might have hapened is you gave more than ei100 exposure and on top of that overdeveloped for 7 minutes: both my shots and copies came quite good for me at 1:30 to 3:00 minutes.
my recomendation is to develop by observation with some good safelight.
to avoid damagind the "lovely" thingies i use to hang it in a becker using the proper pincer/cliper/hooksy-thingisy for x-rays: they make a tiny dot in the emulsion but the handling and drying are way easy.
i am planing start shooting LF x-ray soon and my idea to avoid damage is to make vertical, very thin (like an inch or so) tank with aquarium glass to be able to hang the film and make some sort of agitator (perhaps those magnectic stirrers?) to keep the dev moving: move the liquid, not the solid
