This is no time for speculation.
I take it that you have your PR, but your partner has not, and you want to sponsor his later? That process will take some time.
If I were you I'd consult with an immigration lawyer, to sort out your options.
He may be able to get you "off the hook" for not declaring your marriage in your PR application, since to do so might have been dangerous in Lebanon. I would not want to rely on the discretion of employees in the Canadian Visa Office in Lebanon; what if someone spoke out of turn? He/she might lose his job, but you could suffer a far worse fate. This alone might be justification in Canada's eyes for your not declaring your marriage.
Or, the lawyer might advise you to say nothing, let your partner apply for PR on his own, and then you marry again in Canada. He could advise you whether this would be fraudulent or not. After all, all would be OK if you both had obtained PR independently, then married. The only difference here is that you married first, in Spain. Not a substantive difference to Canada, I'd imagine, but it's best to check with a lawyer.