How to pull files from almost bricked android device? (Common suggestions didn't work) I'm new to super user, so please be nice.

My mom has an Odys Rise 10 android (lollipop) tablet, which now fails to boot. All it is doing now is to boot into recovery mode. Before I try to do a factory reset I want to pull all her photos from the device (Yes, I told her about regular backups, but... you know.).

I can use the ADB to connect via USB to the tablet, status is 'recovery'. I can send command to reboot, but I can neither start the shell nor pull files from the tablet. The error says no such file / file does not exist. I assume that the USB debugging is disabled. The device is not accessible via fastboot. Installing custom recovery (e.g. CWM) did not work since I couldn't find a build for the Odys tablet.

But: I can push files into the /system/ folder, so an option could be to push in an altered build.prop with debugging enabled. Unfortunately, I have no original build.prop as a template.

Is it possible to write a kind of minimum build.prop from scratch that could do the job? Or could I just use a build.prop from a arbitrary android device?

Any other ideas are also welcome.

Thanks for any suggestion.

Update 1:
I pulled a build.prop from another android 5 device (actually a Sony Xperia, since the Odys Rise is apparently a rare kind) to get an impression of the content. Much stuff in there. Has anybody an idea which settings are crucial during recovery mode and thus have to be correct for the bricked tablet? And which build.prop entries are not crucial and can be wrong as long as the recovery mode still works? Before  I start playing with the build-prop I want be be sure that I don not make things worse.

Update 2:
I learned that it might be a bad idea to simply replace the build.prop with a random variant, especially when the build number and model number is wrong. But with a lot of searching and begging I got a full update rom file, which should contain a propper build.prop. The problem now is that I cannot access the rom yet. The img-file is not a zip, and cannot be opened via ext4-unpacker or ext2-explorer. Any suggestions on this issue? Anyone?
So. The question was basically whether it is possible to write a new build.prop to enable usb debugging when no original template is available.

The answer is yes.

I found out that the stock recovery of the tablet is able to show the latest log files, and these logs contain all entries of the build.prop. Or perhaps the default.prop. After I was able to get a rom image of the stock firmware and was able to unpack this, I had a genuine build.prop to compare.

However, this (new) build.prop with enabled usb debugging was not solving my problem with accessing the photos of the bricked tablet. I was in fact able to push this build.prop into /system folder, but without any effect. But that is subject of another question / thread.