Razmir has long considered at what price he would be prepared to sell His services to the Church of Asmodeus, when comes the Great Avistani War. His status as the only free Evil ninth-circle wizard gives him excellent leverage to demand a high price, but He is well aware that involvement on that side would cost Him his realm and the vast majority of His servants, not to mention presenting a significant risk to His existence as an entity capable of engaging in experiences other than agony.

When the servants of Asmodeus come to negotiate with Him, therefore, He has a contract drawn up by an Axis firm to present to them.

... Not a contract to sell His spellcasting services or rent His nation's army. A contract to have them pay all the costs of the negotiation however it ends, including paying for His time at His opportunity cost and paying all costs associated with His choice of Axis firm to negotiate the contract He actually wants.

When they agree, He knows they're serious.