The Alpha Delta 4 position coax switch is specified as >60 dB isolation.
Your switch is before your linear so the drive will be less than 100 watts or 50 dBm. With 60 dB of isolation the RSP should see -10 dBm or less which is a safe level. I would test it by turning your transceiver power as low as it will go – lets say 1 W or 30 dBm and put out out a CW signal at this level. Then measure in SDRuno the power level you are seeing leaking through the switch. With 60 dB isolation it should be -30 dBm or less in SDRuno. If that is the case you are OK at 100W.