It is possible to connect to a server which has more than 32 devices in its JTAG chain in Vivado. You need to provide option max-jtag-devices at the startup of hw_server to enable the ability to detect more devices in a scan chain. The default value for this setting is 32. Note that increasing this number will slow down the device discovery process which in turn can slow down cable access.
Specify the max-jtag-devices option at hw_server start-up as follows:
hw_server -e "set max-jtag-devices 64"