Don’t feel like you have to memorize everything in the book, and you’ll be able to go through it a bit faster 
You can try and memorize vocab before doing a lesson, but you definitely don’t have to have “mastered” that vocab before reading anything!
For example you could decide to try drilling the vocab for a lesson one week, then start that chapter the next week. Set a time frame for going through the chapter (eg. 1-2 weeks should be fine if you can study a bit every day after work), and use the vocab list like a dictionary when you need it.
(I think there’s a study group on discord if I’m not mistaken, which you might find helpful)
Don’t feel like you need to have 100% mastered every grammar point either - jump into beginner reading resources as soon as you feel comfortable (that depends on you, but many people struggle less after Genki 1). Keep going with Genki 2 (or another book if you want to change) and keep reading level-appropriate materials.
Reading extensively will help reinforce grammar and vocab, and you can always refer back to your textbook when you need to.
There’s a great thread in the forums about getting started reading, you don’t have to wait to be fluent!
I also highly recommend joining the book clubs - it’s nice to read along with others. The Doggy Detectives club just started recently and is quite active (beginners and also some more advanced learners).
But even if a club has finished the book you wanted to read, you can still use the vocab sheets, search for answers to your questions, and ask new ones if no one else already asked - people still reply to those threads. 