Hi Nikhil,
What i understand is that you want to record a call which involves 2 endpoints and IPVCR.
Here this call becomes mulitparty call as more than 2 party is involved i.e 2 endpoints and IP VCR.
To record such call you can either use multisite option and call IP VCR, once endpoint is alreay in call with desktop participant.
Alternatively you can use MCU and configure the conference factory to achieve the same.
Hope this helps
Regards,
Sagar