Unfortunately, you probably wont be able to get multicast to work with this MLAG setup. If we look at the features synchronized between MLAG peers, IGMP snooping is not one of them. Page 1023: [URL] the following white paper indicates that MLAG does not meet the criteria for passing multicast traffic, and suggests to instead use a stack setup. Page 14: [URL] 
We have been moving to the DELL 4032f  MLAG connected switch as the core of a CCTV network with a Cisco 4510 as a LAG connection to the older network.  We can not seem to get MULTICASTING traffic to pass over the DELL to CISCO LAG link.  Multicast groups show up on DELL side of port channel but not the Cisco Side so CISCO side of network never seems to see the multicast traffic  CISCO MULTICAST GROUPS 4510#sh ip ig snooping groups vlan 27Vlan Group Version Port List---------------------------------------------------------27 239.1.1.1 v2 Te2/3, Po227 239.1.1.2 v2 Te2/3, Po227 239.1.1.3 v2 Te2/3, Po227 239.1.1.4 v2 Te2/3, Po2 TE2/3 edge cisco switch old CCTV core Po2 port channel to another Cisco switch with subscriber to stream  ip querier configured on DELL n2024 edge switch connected to the MLAG 4510#sh ip ig snooping querier vlan 27IP address : 172.28.232.2IGMP version : v2Port : Po1Max response time : 10s Po1 port channel to the DELL 4032f MLAG switch no groups   DELL primary vpc switch 2-4032f#show ip igmp snooping groups vlan 27 Vlan Group Type OIFs---- ----------------------- ------- ----------------------------------------27 224-239.129|1.1.1 Dynamic Po1,Po727 224-239.129|1.1.2 Dynamic Po1,Po727 224-239.129|1.1.3 Dynamic Po1,Po727 224-239.129|1.1.4 Dynamic Po1,Po727 224-239.168|40.168.168 Dynamic Po1,Po7 Po1 port channel interlink port channel of MLAG Po7 port channel port channel to CISCO 4510 switch  2-4032f#show ip igmp snooping querier vlan 27 Vlan 27 : IGMP Snooping querier status----------------------------------------------IGMP Snooping Querier Vlan Mode................ DisableQuerier Election Participate Mode.............. DisableQuerier Vlan Address........................... 0.0.0.0Operational State.............................. DisabledLast Querier Address........................... 172.28.232.2Operational version............................ 2Operational Max Resp Time...................... 11    DELL vpc secondary switch 4-4032f#show ip igmp snooping groups vlan 27 Vlan Group Type OIFs---- ----------------------- ------- ----------------------------------------27 224-239.129|1.1.1 Dynamic Po1,Po2327 224-239.129|1.1.2 Dynamic Po1,Po2327 224-239.129|1.1.3 Dynamic Po1,Po2327 224-239.129|1.1.4 Dynamic Po1,Po2327 224-239.168|40.168.168 Dynamic Po1,Po23 Po1 port channel interlink port channel of MLAG Po23 port channel port channel to DELL switch with subscriber to stream  4-4032f#show ip igmp snooping querier vlan 27 Vlan 27 : IGMP Snooping querier status----------------------------------------------IGMP Snooping Querier Vlan Mode................ DisableQuerier Election Participate Mode.............. DisableQuerier Vlan Address........................... 0.0.0.0Operational State.............................. DisabledLast Querier Address........................... 172.28.232.2Operational version............................ 2Operational Max Resp Time...................... 11  DELL edge switch on connect to MLAG switch on port channel 1 with querier address 4-2024#show ip igmp snooping querier vlan 27 Vlan 27 : IGMP Snooping querier status----------------------------------------------IGMP Snooping Querier Vlan Mode................ EnableQuerier Election Participate Mode.............. DisableQuerier Vlan Address........................... 172.28.232.2Operational State.............................. QuerierOperational version............................ 2Operational Max Resp Time...................... 10   4-2024#show ip igmp snooping groups vlan 27 Vlan Group Type OIFs---- ----------------------- ------- ----------------------------------------27 224-239.129|1.1.1 Dynamic Po1,Gi1/0/15-1827 224-239.129|1.1.2 Dynamic Po1,Gi1/0/15-1827 224-239.129|1.1.3 Dynamic Po1,Gi1/0/15-1827 224-239.129|1.1.4 Dynamic Po1,Gi1/0/15-1827 224-239.168|40.168.168 Dynamic Po127 224-239.255|127.255.250 Dynamic Gi1/0/11
IGMP snooping multicast issue DELL 4032f MLAG connection to Cisco switch