If MAN genuinely aspires (amongst other things) to be a credible alternative point of entry to the UK to LHR, it will be difficult for it not to offer these types of facilities.
If there is not enough demand from individual airlines (e.g. CX at daily A350 is not close to the MEB3's multiple daily departures) the airport should seek to facilitate an alternative solution. Whether that's a MAG solution (e.g. 1903 in T2) or an alliance based one (e.g. OW lounge) it should be on their radar.