could he be cheating by going to a party bus?

my husband and i separated for a mth, that mth was my bday, and he took off during my bday. we were 1st working it out before my bday, but during the week of my bday, he immediately stop talking to me. and then started begging for me back after a mth -_- i eventually went back to him. i was using the comp to check my email, but his was still signed in. i saw a party bus email, clicked on it and it was a receipt on the day of my bday at 10am. ive talked to him about it and he said it wasnt him. he was mad and blamed that it was me who went since its on my bday. he said none of the credit cards he owns doesnt end in the last 4 digits that was showned on the receipt. if it was me that went, i wouldnt be stupid enough to put his email and name on it, like wtf, he thinks im that stupid. and he would confront me beforehand. if i never saw this email, hed never say a thing about it. yes, none of his credit cards ends in those 4 digits, but he must have used someone elses. does party buses have drinking parties or strip clubs in the morning? or he just purchased it before going?