If a signal is too weak to open the squelch then it will be way to weak for close call to pick it up. The squelch setting should not make any difference.
A squelch setting of 2 open on a -115dBm signal and a setting of 15 still opens to a -90dBm signal. CloseCall activates on -57dBm and stronger signals. So squelch settings do not matter.
22. Close Call Sensitivity (No Modulation)
ITEM UNIT NOMINAL LIMIT
40.840 MHz dBm -53 -30 Max (NFM)
72.515 MHz dBm -54 -30 Max (NFM)
127.175 MHz dBm -54 -30 Max (AM)
161.985 MHz dBm -54 -30 Max (NFM)
272.950 MHz dBm -54 -30 Max (AM)
406.875 MHz dBm -52 -30 Max (NFM)
857.150 MHz dBm -52 -30 Max (NFM)
1299.925 MHz dBm -57 -30 Max NFM
Squelch is irrelevant for close call. The lower you set it, the weaker, more distant signals you pull in which serves an opposite purpose versus close call