I think this has been discussed several dozen times before, I will answer you once again.
First, we know that PL-15E is about 4 meters in length, the one in the photo above is only about 2 meters. Warhead lost, what can you do with the engine and fuel compartment? At the worst case, India recovers the warhead of that missile, it's a PL-15E, the export version of PL-15. Do you think that everything in the export version is the same as the domestic version? In case India wants reverse engineered the PL-15E, I'd suggest them to do that with Meteor which is considered more advanced.
Conclusion: India didn't lose to J-10C or PL-15E but lost to its pilot training, hardware maintenance and combat doctrine. Not a few words can describe all.
PS. The truce is so fragile, and the two nations will not ceasefire that easily. More violations to the truce are on the way, more fighting expected. Just not sure how things may happen.