Were you able to solve this?
Running into a similar issue with my self-made library. Mine is not on github but located in the folder with my app that I am trying to deploy.
devtools::install(file.path(getwd(),'MyPackage') )
library(MyPackage)
# results in this:
"C:/PROGRA~1/R/R-35~1.1/bin/x64/R" --no-site-file --no-environ --no-save --no-restore --quiet CMD INSTALL \
"N:/Research/myapp/MyPackage" --library="C:/Users/myname/Documents/R/win-library/3.5" \
--install-tests
#more code on the package install....
#running the app
runApp('N:/Research/myapp/myapp')
Preparing to deploy application...DONE
Uploading bundle for application: 396647...Error in yaml::yaml.load(string, ...) :
Parser error: while parsing a block mapping at line 1, column 1 did not find expected key at line 4, column 41
Calls: <Anonymous> ... tryCatch -> tryCatchList -> tryCatchOne -> <Anonymous>
Execution halted
My R library is stored as MyPackage_0.10.3.tar.gz with the DESCRIPTION, INDEX,LICENSE,NAMESPACE files as well as several folders (data,doc,html,help,etc). Looks like the library is still downloading locally...? Installing the package and working locally works fine.