I think their advice is very good.
As I have mentioned in other replies, an important thing is to tell her that you love her, and will NEVER ever use it as an excuse to cheat on her. That is one fear or concern many beginning women have. Since you cannot satisfy her sexually with intercourse, let her know that it is just as important to YOU as it is to her for her to be satisfied. Having another man satisfy her would be a solution that you would approve of.
Since you will be giving her permission, she should not feel that she is cheating on you/ being unfaithful/ or hurting your marriage.
I do hope that she is open to you performing oral sex on her. If not, see if you can pleasure her by caressing her nipples, sucking on one at the same time, and then while still sucking on a nipple, finger her pussy and clit. She is bound to have multiple orgasms. If that works out, see if you can progress to oral sex instead of using your finger(s).
Of course there are all types of other sexual possibilities.
