A1409 is a simultaneous dual band router. This means that both the 2.4 GHz and 5 GHz bands are providing a signal with the same wireless network name.
If your camera will not connect to the WiFi network provided by your Time Capsule, then you can try the following:
Open up AirPort Utility on your Mac
Click on the Time Capsule to select it
Click Edit in the smaller window that appears
Click the Wireless tab at the top of the next window
Click the Wireless Options button near the bottom of the window
Enter a check mark in the box next to 5 GHz name
Click Save, then click Update to save the new setting.
Now, your Time Capsule is providing two separate networks with two different names. The 2.4 GHz network is the name that you have been using all along. The 5 GHz network name now has "5 GHz" added to the name.
"Point" the camera at the 2.4 GHz network to see if it will connect to a 2.4 GHz signal.
Your other WiFi devices will connect to the 2.4 GHz network as well.......unless......you point them at the faster network that is using 5 GHz.
5 GHz works well if devices are in the same room or close proximity to the Time Capsule. The 2.4 GHz connection will be better if devices are located further away.......since the 2.4 GHz network is stronger (but slower) than the 5 GHz network.
Obviously, it is much simpler to use the Time Capsule in its default setting of providing both 2.4 GHz and 5 GHz signals using the same network name and then letting devices connect to the best signal automatically.
But, if your camera cannot connect to a dual band network, your options become more complicated.
Finally, a note to point out that an A1409 Time Capsule is at least 7 years old and as much as almost 9 depending on when it was placed into service. The average useful life of this version was about 5-6 years, so realistically it is probably time to start to think about a new router.