I have this strange but weak theory, built on the basis of rumours.
Some member here suggested a few days ago that Usa actually offered us F-15 during PM visit to USA in july (june or whatever).
But there were some serious conditions which led to us ignoring the deals completely. This offer could be a political move to drag us back to tables to compromise CPEC, Afg Peace talks and pressurize us into actually buying F-15 against Rafales. There is no doubt that if India actually gets F-15, a whole other level panic will be created. However, I believe that it is impossible that India will buy these Eagles, they already have huge fleet of Dual Engine MKIs and also going the Rafale route.
MRCA tender was for medium weight, single engine preferred fighters. F-15 doesn’t fit in, but one can also consider what a deal of just 30-40 F-15s initially can provide to india in terms of technology as well as in longer terms the support to integrate future weapons of USA which are always promising