Duplicate ‘Courses’ Admin Menu conflict?

Hello,
I am in the process of testing LifterLMS on a staging site to see if it will meet our needs. We have a custom theme (built by a developer who is no longer on the project). When I try to edit a blank lesson within a course, the page refreshes but stays on the course edit page. I noticed that there is no Lessons sub-tab under Courses in the admin menu. I wondered if this is because our theme already has a Courses item in the menu.

I tried adding the code recommended for fixing the conflict with Caldera Forms, thinking it might be a similar issue, to functions.php but had no luck. I also tried the llms customizations plugin with the same code plus the action to delay the initialization until after plugins have loaded, no change. I am new to PHP so I may not have done these correctly. Any help would be much appreciated. Please let me know if there is any other info you need from me. Thanks!

Nick

Wordpress
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Home Url: http://buphx.staging.wpengine.com
Site Url: https://buphx.staging.wpengine.com
Version: 4.7.4
Debug Mode: No
Locale: en_US
Multisite: No
Page For Posts: Not Set
Page On Front: Not Set
Permalink Structure: /%year%/%monthnum%/%day%/%postname%/
Show On Front: posts
Wp Cron: Yes

Settings
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Version: 3.7.6
Db Version: 3.7.6
Course Catalog: Online Courses (#1392)
Course Catalog Per Page: 9
Course Catalog Sorting: menu_order
Membership Catalog: Membership Catalog (#1393)
Membership Catalog Per Page: 9
Membership Catalog Sorting: menu_order
Site Membership: Not Set
Student Dashboard: My Courses (#1395)
Courses Endpoint: my-courses
Edit Endpoint: edit-account
Lost Password Endpoint: lost-password
Vouchers Endpoint: redeem-voucher
Autogenerate Username: yes
Password Strength Meter: yes
Minimum Password Strength: strong
Terms Required: no
Terms Page: Not Set
Checkout Names: required
Checkout Address: required
Checkout Phone: optional
Checkout Email Confirmation: yes
Open Registration: no
Registration Names: required
Registration Address: optional
Registration Phone: hidden
Registration Voucher: optional
Registration Email Confirmation: no
Account Names: required
Account Address: required
Account Phone: optional
Account Email Confirmation: yes
Checkout Page: Purchase (#1394)
Confirmation Endpoint: confirm-payment
Force Ssl Checkout: no
Country: US
Currency: USD
Currency Position: left
Thousand Separator: ,
Decimal Separator: .
Decimals: 2
Trim Zero Decimals: yes
Recurring Payments: yes 
Cert Bg Width: 800
Cert Bg Height: 616
Cert Legacy Compat: no

Gateways
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Manual: Disabled
Manual Logging: no
Manual Order: 1

Server
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Mysql Version: 5.6.35
Php Curl: Yes
Php Default Timezone: America/New_york
Php Fsockopen: Yes
Php Max Input Vars: 3000
Php Max Upload Size: 32 MB
Php Memory Limit: 512M
Php Post Max Size: 32M
Php Soap: Yes
Php Suhosin: No
Php Time Limt: 300
Php Version: 5.6.30-1+wpengine8
Software: Apache
Wp Memory Limit: 40M

Theme
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Name: BU PHX
Version: 0.1.0
Themeuri: 
Authoruri: 
Template: buphx
Child Theme: No
Llms Support: No

Plugins
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Advanced Custom Fields PRO: 5.5.10
Gravity Forms: 2.2.2
Gravity Forms Coupons Add-On: 2.6
Gravity Forms Stripe Add-On: 2.3
GravityView - Gravity Forms Import Entries: 1.3.2
LifterLMS: 3.7.6
LifterLMS Customizations: 1.0.0
My Eyes Are Up Here: 1.1.8
Nested Pages: 1.6.8
Redirection: 2.5
Sortable Posts: 1.1.3
User Roles and Capabilities: 1.2.1

Integrations
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BbPress: No
BuddyPress: No