Locked Android Tab

I know this question has already been asked, but I feel like it has not been fully answered.

I own a Acer Iconia One 7. It is locked with a pattern and only 2 trials are remaining before data will be erased.

I HAVE TO get the data back.

I have tried many ways to unlock it, but for each there is a problem which is not described anywhere.

1- Update the tab from SD card (with recovery mode), implement Pattern-password-disable.zip ( as described in https://forum.xda-developers.com/showthread.php?t=2244741 ). The installation is aborted (Error code : 7, no footer).

2- Install aromafm from SD card (with recovery mode), in order to further access and remove the appropriate files. The installation is aborted (Error code : 7, no footer).

3- Use ADB Update. I installed the tool on my computer, but there is no connexion with my tab. When I tape "adb devices" in the command line, the list remains empty, in all different states of the tab (power off, power on, recovery mode, waiting for adb update...)

4- Make a backup on sd card, then open the backup. It seems to be a way to open it ( https://sourceforge.net/projects/adbextractor/ ) but I can not find how it works at all ( I installed a java program... but then ? despite all my searches... ).

5- try many patterns and recover my backup with 2 remainings trials each 2 trials. I hope I won't have to go there...

6- Use online google's tool to unlock my tab, As my google account is logged in on the tab. The tool knows the tab, but no connexion is made (flight mode activated. Is there a way to disable flight mode?).

7- I could try to set a data factory reset, then try to get the data back with some appropriate softwares. But no confidence at all.

As y ou can guess I'm a bit bored with this. I feel like the impossibility of removing patterns with google account password is a big security failure, as it will make me set no pattern at all on my next tab.

So my question is : which way is the best? Do I have any chance to get my data back?