it's not that it's a setback. it's more like the indians were overestimating their relationship with the US. they failed to realize the US has reached maximum war fatigue and needs to vacate Afghanistan. The only way they can avoid fall of Saigon scenario is for Pakistan to manage Afghanistan, hoping that it stays quiet after they leave. I'm surprised at the stupidity of indian planners, they literally thought they owned the US.
If Pakistan is helping to negotiate peace deal in the neighboring country, it should push for economic aid as reimbursement for the damage it has caused to the country. it should probably demand more and tie it directly to stability in Afghanistan. The only thing it should do differently, is NOT use those funds for military hardware acquisitions as it proves incorrect use of funds. This was one of the main reasons why the funding was cut off.
Rather, it should use that money to develop FATA & Balochistan, enhance connectivity thru out these regions, build schools, trade zones, etc. This will significantly get rid of grievances of the region towards Eastern Pakistan which has traditionally received lion's share of development funding. This will also help reduce terror by improving lives of those in the region, which will hold water in congressional or senate debates. This will secure long-term source of funding and can help build the tribal areas and frontier regions. I'm sure EU will also join in to fill the gap in funding. At the same time, it can push for investment in these areas as well as waiver from tariffs on all products manufactured there.