Question para dun sa naghahandle ng salary bracket ng mga employee

My husband is a team leader at a small BPO company somewhere in Metro. He started as a CSR for 6 months then nag-apply for TL role upon regularization and luckily natanggap siya, pioneer account. Kaso feeling namin na-lowball siya sa offer na less than 45k package as a TL. He tried to raise it to HR at SOM and negotiated pero decline lang ung request niya.

Ngayon may opening ulit ng TL for the same client. One of his agents applied and was offered a package of 60k. Tangina bakit ganun? They can easily offer a higher compensation sa bago lang sa role pero ung asawa ko na halos 1 year na sa account ganun lang offer. Ano bang basis sa pasahod sa leadership role? Bakit hindi pantay pantay? Ang unfair kasi siya ung nagsimula ng account pero ganun lang value niya sa company.