Extra Long Window Guards??

[Howard Rubin]

We have an apartment complex in a state where we are required to have tenants sign Window Guard forms and for the first time in decades, a tenant asked about getting window guards.  The issue is that we can't find window guards that would work/fit these windows.  

See photo below.  The large center pane is fixed, the left and right panes are horizontal sliders. We technically would only need to guard the left and right panes, but there is obviously nothing to affix a window guard to on the window itself. The width of the entire wood frame, left to right, is 106”. There is a second smaller window in the bedroom, that has the exact same layout (fixed center pane, horizontal sliders on the left and right).

Does anyone have any idea for a window guard that would work or how to secure a regular window guard with these types of windows?

Thanks!