H520, ETx gimbal problem

Hi!
So, this drone was crashed and got into my hands after mechanical repairs were done in the field but the gimbal/camera were still dead. There's no official service available around and frankly it's cheaper for a client to buy a new camera setup anyway, so I got it for a DIY-repair attempt (note that I'm not an expert technician in a commercial drone game, but I have some background in control systems software, uav design and such). There was a visible tear damage in a datalink flex connection around the gimbal shaft in the camera casing, so I gently disassembled the camera module and got it off the shaft to get that cable out enough to fix it and after some wild hours over the microscope (never did micro before) I managed to restore 4 damaged tracks and reassemble everything back in one piece. So far so good, I got camera/thermal feed back on the remote but the gimbal is clearly unhappy about something else. When the drone is powered on, it does this dance in the loop, if I try to initiate gimbal calibration it just goes limp and never shows any progress.
I already sent the drone over, so the main question would be if this is something that still can be dealt with on spot or does it absolutely need official service software to recalibrate/debug or something like that? Additionally, is there a possibility to lock the gimbal in the settings or switch it off and lock it mechanically so that the thermal can still be used in fixed position (might be obvious, but again, not a pilot myself )?
Thanks in advance!