I will be flying Airasia in to Cebu from Kuala Lumpur, ticket price is similar to yours (add 20kg luggage and price goes up). One good thing with KLIA2 Airport in KL is they have a hotel within the International zone which is pretty cheap if you book it through the Airasia-website, if you do it in the airport it is more expensive but ther you can pay an hourly rate if more convenient. I used this on a VISA-run once and it worked pretty good.
The military exchange, AAFES has a travel agency website. Your Star Card can be used for payment. You don’t have to pay the $29.00 annual fee if booking hotels and flights. The fee is for sea cruises. www.govvacationrewards.com
Of course. Anything can be bought. But the chances of the stamp being fake, you getting caught with that fake stamp and then being thrown in the foreigner prison in manila aren't exactly zero (and you absolutely should be thrown in prison for faking/giving a bribe for a stamp). Do it the right way. Anyone who gives you illegal advice had better do so through private message. This forum is not about encouraging illegal behavior.
Sama-Sama Express KLIA Airside Transit Hotel https://www.airasiago.com.my/Sepang-Hotels-Sama-Sama-Express-KLIA-Airside-Transit-Hotel.h10945921.Hotel-Information?chkin=21/03/2019&chkout=22/03/2019&rm1=a2&star=50,30&sort=recommended&hwrqCacheKey=3927d6ab-343d-4aa0-8305-5ebde5be03e9HWRQ1553186576640&cancellable=false®ionId=5002571&vip=false&c=9b9bd319-da86-4224-b082-fb6296cf6b90&&exp_dp=280&exp_ts=1553186575918&exp_curr=MYR&swpToggleOn=false&exp_pg=HSR Not sure if the link works for you. Btw, I have always got a stamp in my passport in KL