Here is a howto to bring German Telekom IPTV (Magenta TV) to work with Mikrotik:
https://cv.skuzzle.de/magenta-mikrotik/
and
https://administrator.de/contentid/667348
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Look for IGMP Proxy https://wiki.mikrotik.com/wiki/Manual:Routing/IGMP-Proxy
and PIM-SM https://wiki.mikrotik.com/wiki/Manual:Multicast_detailed_example#IGMP