2013 Ford Edge: Soft break pedal and brakes after hard-ish stop

So I was driving at around 30mph when someone in the opposite lane pulled a left turn right in front of me and I had to make a fairly hard stop to avoid a collision.

I noticed immediately afterward that my breaks had gone from very firm and responsive to extremely soft, such that I have to push the pedal to the floor to even start slowing down. No warning lights on the dash came on. Pumping the breaks does help with stopping but when I tried doing it while in park as some google articles suggested, it didn't help. I did notice a light whoosing(for lack of a better term) coming from the pedal when I released it. I hadn't noticed this sound before but maybe I just didn't have a reason to pay attention until now.

I'm not a car person and have no experience working on cars so I took it into a local shop. Their inspection came back that my pads are fine, brake fluid quantity and quality is fine, and no external hydraulic leaks were found. They did not say what they think the issue is but their suggested fix is to fully replace the ABS hydraulic control unit which they quoted at about $2300 for parts and labor ($1250 for the hcu part and about $680 for labor plus another $400 to flush the system afterwards).

I'm worried they're just charging me for the maximum repair because they could probably tell I'm not car savvy but I really just don't know enough to say for sure.

I would really appreciate any advice on how to deal with this and if this solution/price seems reasonable.

Thanks in advance.

(I'm considering trying another shop but I wouldn't feel comfortable driving the car so I would need to get it towed and am concerned I would spend all the extra time and money for a similar result if the HCU does indeed need to be replaced. Also, I'm new to the area and don't have a trusted shop here yet so it feels like a gamble no matter where I go)

Edit: Just want to keep this updated incase anyone has the same issue and stumbles onto this post.

So, after reading the replies below I did a couple more hours of research into master cylinder and brake booster issues with Ford Edges.

What I found is that a large proportion of people who have had similar symptoms to what I described almost always had to change the ABS HCU, eventually. People would change the cylinder and/or the booster only to end up back in the shop a few weeks later with the same issue and find out the problem was the ABS HCU the whole time. I also was able to find that the cost I was quoted for this work, while on the high end, is still pretty typical and I live in an area where the costs are going to be higher than average.

So, I've authorized the work. The shop I went to is highly rated and I'm more comfortable now that I've done some research and it seems like they actually had the experience to know what the root cause of the problem was. And the price seems fair for my area. I'll update again once the work is finished and I'm back in the road.

For reference, I found carproblemzoo.com and the ford forums to be the best resources for researching issue and problem history with my make/model. Hope it helps.