Is it permissible to change a vow to slaughter a camel to slaughter a cow or something similar due to fear of the Coronavirus pandemic, knowing that the time for fulfilling the vow has passed?

Undertaking a vow is disliked (makrooh), but it becomes obligatory to fulfill it if it is an act of obedience to Allah. The general principle is to fulfill the vow as it was made. If fulfilling it becomes impossible due to a genuine fear of illness or similar circumstances, then it is permissible to wait, or to substitute it if it is highly probable that the situation will persist. However, it is necessary to verify the widespread nature of the illness. Some scholars are of the opinion that it is permissible to switch to something better, even if the fulfillment of the vow is not impossible. Based on this, it is permissible to slaughter a cow equal in value to a camel if it is more beneficial and safer from illness.