There is no fix for that kind of damage. The speaker will need to be reconed, if you can find a specialist that does that kind of work. Your best bet is probably to find a replacement on ebay. It may require buying an entire speaker that you can harvest parts from.
Madisound madisoundspeakerstore.com they sell repair kits and replacement drivers. If they have your speaker model in their database, you may be able to get replacements that fit. The main problem with old drivers is the rubber or foam surround failing or plastic cone material gets brittle and weak. Another potential problem area is capacitors in the crossover... some types fail over time due to the materials used in them breaking down just from age. Madisound also has crossover repair kits last time I looked. If you find an equally old pair of speakers and the cones don't look like the one in your photo... just wait, it won't be long before they DO look like the ones in your picture. If you put old drivers in your speaker expecting a long term repair, you're going to be badly disappointed, because those old drivers aren't going to be much different than your broken ones. If you replace 1 broken driver in 1 speaker, consider replacing the same driver in the other speaker also... that keeps the sound more consistent between the 2 speakers. Unless that's not important to you... if you just want those speakers working with not much regard for sound quality... just replace what's obviously broken.
Take the speaker out by removing the four screws and gently remove it from the cabnet. Inspect the back of the speaker closely for any tags or numbers. If you can identify the speaker from anything printed on the back, google that number/whatever and see if it can lead you to a replacement.
Alternatively contact Infinity customer support here,
These speakers sold for around $900 MSRP/pr but were often sold for much less. They are NOT made with premium components... everything about this speaker has modest updates from entry level models. There's no real issue with putting in a replacement driver that is not identical to the original at this point in the life of these speakers. If you just want them to work, replace any non-working drivers. If you want them to sound good, if you replace the midrange driver in 1 speaker, replace the same driver in the other speaker (ditto for woofers or tweeters). These are already 15 years old or more, so most everything that synthetic (plastic or "rubber" or "foam") is in the process of breaking down and it's not uncommon for all the drivers to fail in some way. Sometimes it is because the glue they used in the drivers disintegrates over time. Other times, rubber parts get hard and lose flex over time. And speakers with foam surrounding the cones (rather than rubber) typically experience decomposing foam, where it is literally falling apart by itself. Infinity was a high end speaker company from 1968 until it was sold to Harman International in 1989. The previous high-end models designed by Nudell disappeared immediately or within a few years and were replaced with models that never performed like "real" Infinity speakers designed by Nudell. In 2017 Harman International was bought by Samsung.